Compare commits

..
Author SHA1 Message Date
Eugene Yurtsev 0b8634b4c6 x 2025-06-25 10:25:06 -04:00
Eugene Yurtsev bc3ef7f913 x 2025-06-24 14:47:20 -04:00
Eugene Yurtsev 0dda1b4b1e x 2025-06-24 12:35:31 -04:00
Eugene Yurtsev d22c2c4dac x 2025-06-24 11:17:21 -04:00
Eugene Yurtsev db03dccb2b x 2025-06-24 09:56:19 -04:00
Eugene Yurtsev c79c9ea733 x 2025-06-20 17:06:13 -04:00
Eugene Yurtsev b115e1dcde tools 2025-06-20 17:04:41 -04:00
Eugene Yurtsev 3b59213311 fix tools 2025-06-20 16:45:24 -04:00
Eugene Yurtsev 0c0e5a299d Replace notebook with markdown file 2025-06-20 16:33:42 -04:00
Lauren Hirata Singh 69d4c37d25 Consolidate assistant conceptual guides 2025-06-18 19:05:34 -04:00
Lauren Hirata Singh 0e7554a1a1 Update navigation 2025-06-18 10:58:18 -04:00
Lauren Hirata Singh 596c60a65c Move LGP to platform section 2025-06-18 10:58:12 -04:00
Lauren Hirata Singh e45797ce19 Fix titles based on feedback 2025-06-18 10:49:55 -04:00
Lauren Hirata Singh e746b54a57 Change titles 2025-06-17 16:30:35 -04:00
Lauren Hirata SinghandGitHub c88e22ffa7 Merge branch 'main' into get-started 2025-06-17 16:16:36 -04:00
Lauren Hirata Singh dfdeb6a6f1 Edit stream modes 2025-06-17 15:41:57 -04:00
Lauren Hirata Singh ba08acb71c Fix broken links 2025-06-17 15:21:50 -04:00
Lauren Hirata Singh dd64636ca8 Remove agents/streaming 2025-06-17 15:14:48 -04:00
Lauren Hirata Singh 664475887d Consolidate streaming 2025-06-17 15:07:07 -04:00
Lauren Hirata Singh 3d3a2bfacd edits 2025-06-16 21:07:12 -04:00
Lauren Hirata Singh bbe90e04ca Remove cookie consent popup 2025-06-16 16:35:27 -04:00
Lauren Hirata Singh 905fcb3d02 Fix broken links 2025-06-16 16:25:31 -04:00
Lauren Hirata Singh 543d7d85af Organize existing content differently 2025-06-16 16:17:52 -04:00
408 changed files with 38542 additions and 28783 deletions
+11 -11
View File
@@ -1,29 +1,29 @@
name: "\U0001F41B Bug Report"
description: Report a bug in LangGraph. To report a security issue, please instead use the security option below. For questions, please use the LangChain Forum at forum.langchain.com.
description: Report a bug in LangGraph. To report a security issue, please instead use the security option below. For questions, please use the GitHub Discussions.
labels: [pending,bug]
body:
- type: markdown
attributes:
value: |
value: >
Thank you for taking the time to file a bug report.
Use this to report BUGS in LangGraph. For usage questions, feature requests and general design questions, please use the [LangChain Forum](https://forum.langchain.com/).
Use this to report BUGS in LangGraph. For usage questions, feature requests and general design questions, please use [GitHub Discussions](https://github.com/langchain-ai/langgraph/discussions).
Relevant links to check before filing a bug report to see if your issue has already been reported, fixed or
if there's another way to solve your problem:
* [LangChain Forum](https://forum.langchain.com/),
* [LangGraph Github Issues](https://github.com/langchain-ai/langgraph/issues),
* [LangGraph how-to guides](https://langchain-ai.github.io/langgraph/how-tos/).
* [LangChain documentation with the integrated search](https://python.langchain.com/docs/get_started/introduction),
* [GitHub search](https://github.com/langchain-ai/langgraph),
[LangGraph Github Discussions](https://github.com/langchain-ai/langgraph/discussions),
[LangGraph Github Issues](https://github.com/langchain-ai/langgraph/issues),
[LangGraph how-to guides](https://langchain-ai.github.io/langgraph/how-tos/).
[LangChain documentation with the integrated search](https://python.langchain.com/docs/get_started/introduction),
[GitHub search](https://github.com/langchain-ai/langgraph),
- type: checkboxes
id: checks
attributes:
label: Checked other resources
description: Before submitting this issue, please confirm that you have completed all the steps below by checking each option. These steps help ensure your issue is well-defined, relevant, and actionable.
options:
- label: This is a bug, not a usage question. For questions, please use the LangChain Forum (https://forum.langchain.com/).
- label: This is a bug, not a usage question. For questions, please use GitHub Discussions.
required: true
- label: I added a clear and detailed title that summarizes the issue.
required: true
@@ -38,7 +38,7 @@ body:
attributes:
label: Example Code
description: |
Please add a self-contained, [minimal, reproducible, example](https://stackoverflow.com/help/minimal-reproducible-example) with your use case. Replace this code with your own!
Please add a self-contained, [minimal, reproducible, example](https://stackoverflow.com/help/minimal-reproducible-example) with your use case.
placeholder: |
from langgraph.graph import StateGraph
@@ -78,7 +78,7 @@ body:
attributes:
label: System Info
description: |
Run on your machine: `python -m langchain_core.sys_info`
python -m langchain_core.sys_info
placeholder: |
python -m langchain_core.sys_info
validations:
+13 -4
View File
@@ -1,6 +1,15 @@
blank_issues_enabled: false
blank_issues_enabled: true
version: 2.1
contact_links:
- name: LangChain Forum
url: https://forum.langchain.com/
about: General community discussions, support, and feature requests
- name: 🤔 Question or Problem
about: Ask a question or ask about a problem in GitHub Discussions.
url: https://github.com/langchain-ai/langgraph/discussions/categories/q-a
- name: Feature Request
url: https://github.com/langchain-ai/langgraph/discussions/categories/ideas
about: Suggest a feature or an idea
- name: Show and tell
about: Show what you built with LangChain
url: https://github.com/langchain-ai/langgraph/discussions/categories/show-and-tell
- name: Slack
url: https://www.langchain.com/join-community
about: General community discussions
+8 -12
View File
@@ -1,29 +1,25 @@
name: 🔒 Privileged
description: You are a LangGraph maintainer, or was asked directly by a maintainer to create an issue here. If not, check the other options.
description: You are a LangChain maintainer, or was asked directly by a maintainer to create an issue here. If not, check the other options.
body:
- type: markdown
attributes:
value: |
Thanks for your interest in LangGraph! 🚀
If you are not a LangGraph maintainer or were not asked directly by a maintainer to create an issue, then please start the conversation on the [LangChain Forum](https://forum.langchain.com/) instead.
You are a LangGraph maintainer if you maintain any of the packages inside of the LangGraph repository
or are a regular contributor to LangGraph with previous merged merged pull requests.
Thanks for your interest in LangChain! 🚀
If you are not a LangChain maintainer or were not asked directly by a maintainer to create an issue, then please start the conversation in a [Question in GitHub Discussions](https://github.com/langchain-ai/langchain/discussions/categories/q-a) instead.
You are a LangChain maintainer if you maintain any of the packages inside of the LangChain repository
or are a regular contributor to LangChain with previous merged merged pull requests.
- type: checkboxes
id: privileged
attributes:
label: Privileged issue
description: Confirm that you are allowed to create an issue here.
options:
- label: I am a LangGraph maintainer, or was asked directly by a LangGraph maintainer to create an issue here.
- label: I am a LangChain maintainer, or was asked directly by a LangChain maintainer to create an issue here.
required: true
- type: textarea
id: content
attributes:
label: Issue Content
description: Add the content of the issue here.
- type: markdown
attributes:
value: |
Community members should **NOT** work on Privileged issues unless these issues have been explicitly marked with a "help-wanted" tag.
-31
View File
@@ -1,31 +0,0 @@
Thank you for contributing to LangGraph! Follow these steps to mark your pull request as ready for review. **If any of these steps are not completed, your PR will not be considered for review.**
- [ ] **PR title**: Follows the format: {TYPE}({SCOPE}): {DESCRIPTION}
- Examples:
- feat(core): add multi-tenant support
- fix(cli): resolve flag parsing error
- docs(openai): update API usage examples
- Allowed `{TYPE}` values:
- feat, fix, docs, style, refactor, perf, test, build, ci, chore, revert, release
- Allowed `{SCOPE}` values (optional):
- langgraph, docs, cli, checkpoint, checkpoint-postgres, checkpoint-sqlite, prebuilt, scheduler-kafka, sdk-py
- Once you've written the title, please delete this checklist item; do not include it in the PR.
- [ ] **PR message**: ***Delete this entire checklist*** and replace with
- **Description:** a description of the change. Include a [closing keyword](https://docs.github.com/en/issues/tracking-your-work-with-issues/using-issues/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword) if applicable.
- **Issue:** the issue # it fixes, if applicable
- **Dependencies:** any dependencies required for this change
- **Twitter handle:** if your PR gets announced, and you'd like a mention, we'll gladly shout you out!
- [ ] **Add tests and docs**: If you're adding a new integration, you must include:
1. A test for the integration, preferably unit tests that do not rely on network access,
2. An example notebook showing its use. It lives in `docs/docs/integrations` directory.
- [ ] **Lint and test**: Run `make format`, `make lint` and `make test` from the root of the package(s) you've modified. We will not consider a PR unless these three are passing in CI. See [contribution guidelines](https://github.com/langchain-ai/langgraph/blob/main/CONTRIBUTING.md) for more.
Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to `pyproject.toml` files (even optional ones) unless they are **required** for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
+5 -12
View File
@@ -1,18 +1,11 @@
# Please see the documentation for all configuration options:
# https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
# and
# https://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file
version: 2
updates:
- package-ecosystem: "github-actions"
directory: "/"
schedule:
interval: "weekly"
- package-ecosystem: "pip"
directories:
- "libs/checkpoint"
- "libs/checkpoint-postgres"
- "libs/checkpoint-sqlite"
- "libs/cli"
- "libs/langgraph"
- "libs/prebuilt"
- "libs/sdk-py"
schedule:
interval: "weekly"
-3
View File
@@ -3,9 +3,6 @@ name: CLI integration test
on:
workflow_call:
permissions:
contents: read
jobs:
build:
runs-on: ubuntu-latest
-3
View File
@@ -8,9 +8,6 @@ on:
type: string
description: "From which folder this pipeline executes"
permissions:
contents: read
env:
# This env var allows us to get inline annotations when ruff has complaints.
RUFF_OUTPUT_FORMAT: github
-3
View File
@@ -8,9 +8,6 @@ on:
type: string
description: "From which folder this pipeline executes"
permissions:
contents: read
jobs:
build:
runs-on: ubuntu-latest
-3
View File
@@ -3,9 +3,6 @@ name: test
on:
workflow_call:
permissions:
contents: read
jobs:
build:
runs-on: ubuntu-latest
-3
View File
@@ -11,9 +11,6 @@ on:
env:
PYTHON_VERSION: "3.10"
permissions:
contents: read
jobs:
build:
if: github.ref == 'refs/heads/main'
-3
View File
@@ -7,9 +7,6 @@ on:
paths:
- "libs/**"
permissions:
contents: read
jobs:
benchmark:
runs-on: ubuntu-latest
-3
View File
@@ -5,9 +5,6 @@ on:
paths:
- "libs/**"
permissions:
contents: read
jobs:
benchmark:
runs-on: ubuntu-latest
+60 -12
View File
@@ -3,12 +3,9 @@ name: CI
on:
push:
branches: [main, v1]
branches: [main]
pull_request:
permissions:
contents: read
# If another push to the same PR or branch happens while this workflow is still running,
# cancel the earlier run in favor of the next run.
#
@@ -24,7 +21,7 @@ jobs:
runs-on: ubuntu-latest
outputs:
python: ${{ steps.filter.outputs.python }}
deps: ${{ steps.filter.outputs.deps }}
sdk-js: ${{ steps.filter.outputs.sdk-js }}
steps:
- uses: actions/checkout@v4
- uses: dorny/paths-filter@v3
@@ -39,9 +36,8 @@ jobs:
- 'libs/checkpoint-sqlite/**'
- 'libs/checkpoint-postgres/**'
- 'libs/prebuilt/**'
deps:
- '**/pyproject.toml'
- '**/uv.lock'
sdk-js:
- 'libs/sdk-js/**'
lint:
needs: changes
@@ -59,7 +55,7 @@ jobs:
"libs/prebuilt",
]
if: needs.changes.outputs.python == 'true' || needs.changes.outputs.deps == 'true'
if: needs.changes.outputs.python == 'true'
uses: ./.github/workflows/_lint.yml
with:
working-directory: ${{ matrix.working-directory }}
@@ -78,7 +74,7 @@ jobs:
"libs/checkpoint-postgres",
"libs/prebuilt",
]
if: needs.changes.outputs.python == 'true' || needs.changes.outputs.deps == 'true'
if: needs.changes.outputs.python == 'true'
uses: ./.github/workflows/_test.yml
with:
working-directory: ${{ matrix.working-directory }}
@@ -87,7 +83,7 @@ jobs:
# NOTE: we're testing langgraph separately because it requires a different matrix
test-langgraph:
needs: changes
if: needs.changes.outputs.python == 'true' || needs.changes.outputs.deps == 'true'
if: needs.changes.outputs.python == 'true'
name: "cd libs/langgraph"
uses: ./.github/workflows/_test_langgraph.yml
secrets: inherit
@@ -144,21 +140,73 @@ jobs:
integration-test:
needs: changes
if: needs.changes.outputs.python == 'true' || needs.changes.outputs.deps == 'true'
if: needs.changes.outputs.python == 'true'
name: CLI integration test
uses: ./.github/workflows/_integration_test.yml
secrets: inherit
lint-js:
needs: changes
if: needs.changes.outputs.sdk-js == 'true'
runs-on: ubuntu-latest
strategy:
matrix:
working-directory:
- "libs/sdk-js"
defaults:
run:
working-directory: ${{ matrix.working-directory }}
steps:
- uses: actions/checkout@v4
- name: Setup Node.js (LTS)
uses: actions/setup-node@v4
with:
node-version: "20"
cache: "yarn"
cache-dependency-path: ${{ matrix.working-directory }}/yarn.lock
- name: Install dependencies
run: yarn install
- name: Run lint
run: yarn lint
- name: Build
run: yarn build
test-js:
needs: changes
if: needs.changes.outputs.sdk-js == 'true'
runs-on: ubuntu-latest
strategy:
matrix:
working-directory:
- "libs/sdk-js"
defaults:
run:
working-directory: ${{ matrix.working-directory }}
steps:
- uses: actions/checkout@v4
- name: Setup Node.js (LTS)
uses: actions/setup-node@v4
with:
node-version: "20"
cache: "yarn"
cache-dependency-path: ${{ matrix.working-directory }}/yarn.lock
- name: Install dependencies
run: yarn install
- name: Run tests
run: yarn test
ci_success:
name: "CI Success"
needs:
[
lint,
lint-js,
test,
test-langgraph,
check-sdk-methods,
check-schema,
integration-test,
test-js,
]
if: |
always()
@@ -1,11 +0,0 @@
LangChain
LangGraph
LangSmith
thead
stdio
nd
jupyter
lets
lite
uis
deque
+3 -9
View File
@@ -34,16 +34,10 @@
id: extract_ignore_words
- name: Codespell
uses: codespell-project/actions-codespell@v2.1
uses: codespell-project/actions-codespell@v2
with:
skip: '*.ambr,*.lock,*.ipynb,*.yaml,*.zlib,*.css.map,*.js.map'
skip: '*.ambr,*.lock,*.ipynb,*.yaml,*.zlib,*.md'
ignore_words_list: ${{ steps.extract_ignore_words.outputs.ignore_words_list }}
# We do this to avoid spellchecking cell outputs
- name: Codespell Notebooks
run: make codespell
- name: Codespell LangGraph Library
run: |
# Change to root directory to check the main LangGraph library
cd ..
codespell --skip="*.ambr,*.lock,*.ipynb,*.yaml,*.zlib,*.css.map,*.js.map,*.pyc,__pycache__/*" --ignore-words-list="${{ steps.extract_ignore_words.outputs.ignore_words_list }}" libs/langgraph/langgraph/
run: make codespell
+6 -4
View File
@@ -4,9 +4,11 @@ on:
push:
branches:
- main
- v0
pull_request:
branches:
- main
- v0
workflow_dispatch:
permissions:
@@ -82,9 +84,9 @@ jobs:
run: make llms-text
- name: Build site
run: |
# If this is main branch, then we want to download stats. we do this
# If this is v0 branch, then we want to download stats. we do this
# with the env variable DOWNLOAD_STATS=true
if [ "${{ github.ref }}" == "refs/heads/main" ]; then
if [ "${{ github.ref }}" == "refs/heads/v0" ]; then
DOWNLOAD_STATS=true make build-docs
else
make build-docs
@@ -144,7 +146,7 @@ jobs:
fi
- name: Configure GitHub Pages
if: github.ref == 'refs/heads/main'
if: github.ref == 'refs/heads/v0'
uses: actions/configure-pages@v5
- name: Upload Pages Artifact
@@ -154,6 +156,6 @@ jobs:
path: ./docs/site/
- name: Deploy to GitHub Pages
if: github.ref == 'refs/heads/main'
if: github.ref == 'refs/heads/v0'
id: deployment
uses: actions/deploy-pages@v4
-3
View File
@@ -11,9 +11,6 @@ on:
- cron: "0 5 * * *"
workflow_dispatch:
permissions:
contents: read
jobs:
markdown-link-check:
runs-on: ubuntu-latest
-44
View File
@@ -1,44 +0,0 @@
name: PR Title Lint
permissions:
pull-requests: read
on:
pull_request:
types: [opened, edited, synchronize]
jobs:
lint-pr-title:
runs-on: ubuntu-latest
steps:
- name: Validate PR Title
uses: amannn/action-semantic-pull-request@v5
env:
GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
with:
types: |
feat
fix
docs
style
refactor
perf
test
build
ci
chore
revert
release
scopes: |
checkpoint
checkpoint-postgres
checkpoint-sqlite
cli
langgraph
prebuilt
scheduler-kafka
sdk-py
docs
requireScope: false
ignoreLabels: |
ignore-lint-pr-title
-3
View File
@@ -8,9 +8,6 @@ on:
type: string
default: "libs/langgraph"
permissions:
contents: read
env:
PYTHON_VERSION: "3.11"
+38
View File
@@ -0,0 +1,38 @@
name: JS Release
on:
workflow_dispatch:
jobs:
publish:
# Disallow publishing from branches that aren't `main`.
if: github.ref == 'refs/heads/main'
runs-on: ubuntu-latest
strategy:
matrix:
working-directory:
- "libs/sdk-js"
defaults:
run:
working-directory: ${{ matrix.working-directory }}
steps:
- uses: actions/checkout@v4
# JS Build
- name: Use Node.js
uses: actions/setup-node@v4
with:
node-version: "20"
cache: "yarn"
cache-dependency-path: ${{ matrix.working-directory }}/yarn.lock
- name: Install dependencies
run: yarn install
- name: Build
run: yarn build
- name: Publish package to NPM
run: |
echo "//registry.npmjs.org/:_authToken=${{ secrets.NPM_TOKEN }}" > .npmrc
npm publish
-3
View File
@@ -11,9 +11,6 @@ on:
schedule:
- cron: "0 13 * * *"
permissions:
contents: read
defaults:
run:
working-directory: docs
-45
View File
@@ -1,45 +0,0 @@
name: UV Lock Upgrade
on:
schedule:
# run at midnight every Sunday
- cron: '0 0 * * 0'
# allow manual triggering
workflow_dispatch:
permissions:
contents: write
pull-requests: write
jobs:
upgrade-dependencies:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- name: Set up uv
uses: astral-sh/setup-uv@v6
with:
# use minimum supported Python version
python-version: "3.9"
enable-cache: true
cache-suffix: "uv-lock-upgrade"
- name: Run uv lock --upgrade in all Python packages
run: make lock-upgrade
- name: Create Pull Request
uses: peter-evans/create-pull-request@v7
with:
token: ${{ secrets.GITHUB_TOKEN }}
commit-message: "chore[deps]: upgrade dependencies with `uv lock --upgrade`"
title: "chore[deps]: upgrade dependencies with `uv lock --upgrade`"
body: |
This PR updates the dependencies in all Python packages using `uv lock --upgrade`.
This is an automated PR created by the UV Lock Upgrade workflow.
branch: deps/uv-lock-upgrade
delete-branch: true
labels: |
dependencies
+10 -9
View File
@@ -9,7 +9,7 @@ Here are some things to keep in mind for all types of contributions:
- Follow the ["fork and pull request"](https://docs.github.com/en/get-started/exploring-projects-on-github/contributing-to-a-project) workflow.
- Fill out the checked-in pull request template when opening pull requests. Note related issues and tag relevant maintainers.
- Ensure your PR passes formatting, linting, and testing checks before requesting a review.
- If you would like comments or feedback, please tag a maintainer.
- If you would like comments or feedback, please open an issue or discussion and tag a maintainer.
- Backwards compatibility is key. Your changes must not be breaking, except in case of critical bug and security fixes.
- Look for duplicate PRs or issues that have already been opened before opening a new one.
- Keep scope as isolated as possible. As a general rule, your changes should not affect more than one package at a time.
@@ -20,7 +20,7 @@ For bug fixes, please open up an issue before proposing a fix to ensure the prop
### New features
For new features, please start a new [discussion](https://forum.langchain.com/), where the maintainers will help with scoping out the necessary changes.
For new features, please start a new [discussion](https://github.com/langchain-ai/langgraph/discussions), where the maintainers will help with scoping out the necessary changes.
## Contribute Documentation
@@ -60,7 +60,7 @@ In LangGraph, these are often higher level guides that show off end-to-end use c
Some examples include:
- [Build a Customer Support Bot](https://langchain-ai.github.io/langgraph/tutorials/customer-support/customer-support/)
- [Build a SQL Agent](https://langchain-ai.github.io/langgraph/tutorials/sql/sql-agent/)
- [Build a SQL Agent](https://langchain-ai.github.io/langgraph/tutorials/sql-agent/)
Here are some high-level tips on writing a good tutorial:
@@ -111,6 +111,7 @@ in a more abstract way than how-to guides or tutorials, and should be geared tow
gaining a deeper understanding of the framework. Try to avoid excessively large code examples. The goal here is to
impart perspective to the user rather than to finish a practical project. These guides should cover **why** things work the way they do.
To quote the Diataxis website:
> The perspective of explanation is higher and wider than that of the other types. It does not take the users eye-level view, as in a how-to guide, or a close-up view of the machinery, like reference material. Its scope in each case is a topic - “an area of knowledge”, that somehow has to be bounded in a reasonable, meaningful way.
@@ -186,9 +187,9 @@ Be concise, including in code samples.
## Setup
LangGraph documentation consists of two components:
LangChain documentation consists of two components:
1. Main Documentation: Hosted at [https://langchain-ai.github.io/langgraph/](https://langchain-ai.github.io/langgraph/),
1. Main Documentation: Hosted at [https://langchain-ai.github.io](https://langchain-ai.github.io/langgraph/),
this comprehensive resource serves as the primary user-facing documentation.
It covers a wide array of topics, including tutorials, use cases, integrations,
and more, offering extensive guidance on building with LangGraph.
@@ -249,17 +250,17 @@ make serve-docs
#### Linting
To spell check the docs, run the following from the `docs` directory:
The documentation is linted from the **monorepo root**. To lint it, run the following from there:
```bash
codespell --skip="*.ambr,*.lock,*.ipynb,*.yaml,*.zlib,*.css.map,*.js.map" --ignore-words-list="infor,thead,stdio,nd,jupyter,lets,lite,uis,deque" .
make spellcheck
```
### In-code Documentation
The in-code documentation is autogenerated from docstrings.
For the API reference to be useful, the codebase must be well-documented. This means that all functions, classes, and methods should have a docstring that explains what they do, what the arguments are, and what the return value is. This is a good practice in general, but it is especially important for LangGraph because the API reference is the primary resource for developers to understand how to use the codebase.
For the API reference to be useful, the codebase must be well-documented. This means that all functions, classes, and methods should have a docstring that explains what they do, what the arguments are, and what the return value is. This is a good practice in general, but it is especially important for LangChain because the API reference is the primary resource for developers to understand how to use the codebase.
We generally follow the [Google Python Style Guide](https://google.github.io/styleguide/pyguide.html#38-comments-and-docstrings) for docstrings.
@@ -290,4 +291,4 @@ def my_function(arg1: int, arg2: str) -> float:
This is a description of the return value.
"""
return 3.14
```
```
-10
View File
@@ -47,16 +47,6 @@ lock:
fi; \
done
# Lock all projects and upgrade dependencies
.PHONY: lock-upgrade
lock-upgrade:
@for dir in $(LIBS_DIRS); do \
if [ -f $$dir/Makefile ]; then \
echo "Running lock-upgrade in $$dir"; \
(cd $$dir && uv lock --upgrade); \
fi; \
done
# Test all projects
.PHONY: test
test:
+3 -4
View File
@@ -63,7 +63,7 @@ LangGraph provides low-level supporting infrastructure for *any* long-running, s
While LangGraph can be used standalone, it also integrates seamlessly with any LangChain product, giving developers a full suite of tools for building agents. To improve your LLM application development, pair LangGraph with:
- [LangSmith](http://www.langchain.com/langsmith) — Helpful for agent evals and observability. Debug poor-performing LLM app runs, evaluate agent trajectories, gain visibility in production, and improve performance over time.
- [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform/) — Deploy and scale agents effortlessly with a purpose-built deployment platform for long running, stateful workflows. Discover, reuse, configure, and share agents across teams — and iterate quickly with visual prototyping in [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio/).
- [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/#langgraph-platform) — Deploy and scale agents effortlessly with a purpose-built deployment platform for long running, stateful workflows. Discover, reuse, configure, and share agents across teams — and iterate quickly with visual prototyping in [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio/).
- [LangChain](https://python.langchain.com/docs/introduction/) Provides integrations and composable components to streamline LLM application development.
> [!NOTE]
@@ -73,12 +73,11 @@ While LangGraph can be used standalone, it also integrates seamlessly with any L
- [Guides](https://langchain-ai.github.io/langgraph/how-tos/): Quick, actionable code snippets for topics such as streaming, adding memory & persistence, and design patterns (e.g. branching, subgraphs, etc.).
- [Reference](https://langchain-ai.github.io/langgraph/reference/graphs/): Detailed reference on core classes, methods, how to use the graph and checkpointing APIs, and higher-level prebuilt components.
- [Examples](https://langchain-ai.github.io/langgraph/examples/): Guided examples on getting started with LangGraph.
- [LangChain Forum](https://forum.langchain.com/): Connect with the community and share all of your technical questions, ideas, and feedback.
- [Examples](https://langchain-ai.github.io/langgraph/tutorials/overview/): Guided examples on getting started with LangGraph.
- [LangChain Academy](https://academy.langchain.com/courses/intro-to-langgraph): Learn the basics of LangGraph in our free, structured course.
- [Templates](https://langchain-ai.github.io/langgraph/concepts/template_applications/): Pre-built reference apps for common agentic workflows (e.g. ReAct agent, memory, retrieval etc.) that can be cloned and adapted.
- [Case studies](https://www.langchain.com/built-with-langgraph): Hear how industry leaders use LangGraph to ship AI applications at scale.
## Acknowledgements
LangGraph is inspired by [Pregel](https://research.google/pubs/pub37252/) and [Apache Beam](https://beam.apache.org/). The public interface draws inspiration from [NetworkX](https://networkx.org/documentation/latest/). LangGraph is built by LangChain Inc, the creators of LangChain, but can be used without LangChain.
LangGraph is inspired by [Pregel](https://research.google/pubs/pub37252/) and [Apache Beam](https://beam.apache.org/). The public interface draws inspiration from [NetworkX](https://networkx.org/documentation/latest/). LangGraph is built by LangChain Inc, the creators of LangChain, but can be used without LangChain.
+1
View File
@@ -1,3 +1,4 @@
site/
docs/cloud/reference/sdk/js_ts_sdk_ref.md
.vercel
+9 -3
View File
@@ -1,4 +1,10 @@
.PHONY: lint-docs format-docs build-docs serve-docs serve-clean-docs clean-docs codespell llms-text build-prebuilt tests
.PHONY: lint-docs format-docs build-docs serve-docs serve-clean-docs clean-docs codespell build-typedoc llms-text build-prebuilt tests
build-typedoc:
cd ../libs/sdk-js && yarn install --include-dev && yarn typedoc
cd ../libs/sdk-js && yarn --silent concat-md --decrease-title-levels --ignore=js_ts_sdk_ref.md --start-title-level-at 2 docs > ../../docs/docs/cloud/reference/sdk/js_ts_sdk_ref.md 2>/dev/null
# Add links to the monorepo
sed -e '1,10s|@langchain/langgraph-sdk|[@langchain/langgraph-sdk](https://github.com/langchain-ai/langgraph/tree/main/libs/sdk-js)|g' docs/cloud/reference/sdk/js_ts_sdk_ref.md > temp_file && mv temp_file docs/cloud/reference/sdk/js_ts_sdk_ref.md
build-prebuilt:
# Use to create an update to date prebuilt page.
@@ -15,7 +21,7 @@ build-prebuilt:
fi
uv run python -m _scripts.third_party_page.create_third_party_page stats.yml docs/agents/prebuilt.md --language python
build-docs: build-prebuilt
build-docs: build-typedoc build-prebuilt
uv run python -m mkdocs build --clean -f mkdocs.yml --strict
llms-text:
@@ -39,7 +45,7 @@ vercel-build-docs: install-vercel-deps
serve-clean-docs: clean-docs
uv run python -m mkdocs serve -c -f mkdocs.yml --strict -w ../libs/langgraph
serve-docs:
serve-docs: build-typedoc
uv run python -m mkdocs serve -f mkdocs.yml -w ../libs/langgraph -w ../libs/checkpoint -w ../libs/sdk-py --dirty
clean-docs:
+122 -119
View File
@@ -1,154 +1,157 @@
"""Translate Python markdown to TypeScript and/or consolidate Python-JS markdown into a single document."""
"""Add typescript translation to a given markdown file."""
import argparse
import re
import requests
from langchain_anthropic import ChatAnthropic
# Load reference TypeScript snippets
URL = "https://gist.githubusercontent.com/eyurtsev/e7486731415463a9bc5b4682358859c8/raw/b5a5fda9c7e3387cfcb781f25082814d43675d50/gistfile1.txt"
response = requests.get(URL)
response.raise_for_status()
reference_snippets = response.text
# Initialize model
model = ChatAnthropic(model="claude-sonnet-4-0", max_tokens=64_000)
TRANSLATION_PROMPT = (
"You are a helpful assistant that translates Python-based technical "
"documentation written in Markdown to equivalent TypeScript-based documentation. "
"The input is a Markdown file written in mkdocs format. It contains "
"Python code snippets embedded in prose. "
"Your task is to rewrite the content by translating the Python code to "
"idiomatic TypeScript, using the provided TypeScript reference snippets "
"to ensure accurate and consistent usage (e.g., correct imports, function "
"names, and patterns). "
"Remove the original Python code and replace it with the corresponding "
"TypeScript version. "
"Do not alter the surrounding prose unless a change is necessary to "
"reflect differences between Python and TypeScript. "
"Preserve the structure and formatting of the original Markdown document. "
"Do not make stylistic or structural changes unless they directly support "
"the translation. "
"Use the reference TypeScript snippets as guidance whenever possible to "
"maintain alignment with existing conventions.\n\n"
f"Here are the reference TypeScript snippets:\n\n{reference_snippets}\n\n"
)
CONSOLIDATION_PROMPT = (
"You are a helpful assistant that consolidates parallel Python and JavaScript (TypeScript) technical documentation "
"written in Markdown into a single unified Markdown document. "
"The input consists of two documents: the first is for Python users, and the second is for JavaScript/TypeScript users. "
"Your task is to merge these into one Markdown file using language-specific fenced blocks to separate the content where needed. "
"Use the following syntax to distinguish content for each language:\n\n"
":::python\n"
"# Python-specific content\n"
":::\n\n"
":::js\n"
"# JavaScript/TypeScript-specific content\n"
":::\n\n"
"Follow these consolidation rules:\n"
"- When content (prose or code) is the same or nearly identical in both versions, include it only once—outside of any fenced block.\n"
"- When content differs between the Python and JS versions, wrap each version in its corresponding fenced block.\n"
"- Prefer **paragraph-level separation** of language-specific content. Do not combine Python and JS snippets or terminology in the same sentence or paragraph using conditional phrases.\n"
" For example, avoid inline constructs like:\n"
" `The :::python add_messages ::: :::js reducer ::: function...`\n"
" Instead, write two distinct paragraphs:\n\n"
" :::python\n"
" The `add_messages` function in our `State` will append the LLM's response messages to whatever messages are already in the state.\n"
" ::: \n\n"
" :::js\n"
" The `reducer` function in our `StateAnnotation` will append the LLM's response messages to whatever messages are already in the state.\n"
" :::\n\n"
"- Preserve the overall structure, ordering, and formatting of the original Markdown documents.\n"
"- Do not rephrase or unify content unless it is logically and semantically identical.\n"
"- Use the fenced blocks for both prose and code as needed, and ensure output is clean, readable Markdown suitable for tools that parse these directives.\n"
"Your goal is to produce a cleanly merged documentation file that serves both Python and JavaScript users without redundancy, while maximizing clarity and separation of language-specific details."
)
model = ChatAnthropic(model="claude-3-5-sonnet-latest")
def translate_python_to_ts(markdown_content: str) -> str:
response = model.invoke(
def _get_tqdm():
try:
from tqdm import tqdm
except ImportError:
# If not available return a simple identity function
def tqdm(iterable, *args, **kwargs):
return iterable
return tqdm
_tqdm = _get_tqdm()
opening_pattern = re.compile(r"^\s*```python(?:\s+.*)?\s*$")
closing_pattern = re.compile(r"^\s*```\s*$")
def extract_python_snippets(markdown: str) -> list[str]:
"""
Extract all python code blocks (including their fence lines) from the markdown content.
A python block is defined as any block that starts with a line containing an opening fence
with '```python' (optionally with extra parameters) and ends with a closing fence '```'.
"""
snippets = []
inside_block = False
current_snippet = []
for line in markdown.splitlines(keepends=True):
if not inside_block:
if opening_pattern.match(line):
inside_block = True
current_snippet = [line]
else:
current_snippet.append(line)
if closing_pattern.match(line):
inside_block = False
snippets.append("".join(current_snippet))
current_snippet = []
return snippets
def translate_snippet(python_snippet: str) -> str:
"""Translate a python code block into a TypeScript code block using Langchain.
The response is expected to be a properly fenced TypeScript code block (i.e.
starting with ```typescript and ending with ```).
"""
ai_message = model.invoke(
[
{
"role": "system",
"content": TRANSLATION_PROMPT,
"cache_control": {"type": "ephemeral"},
"content": (
f"You have access to the following up-to-date example TypeScript code "
f"snippets that show examples of building with langgraph "
f"and langchain:\n\n{reference_snippets}\n\n"
"Use this context to translate the following Python code to equivalent "
"TypeScript. Ensure that your output is a valid fenced TypeScript "
"code block (i.e. starts with ```typescript and ends with ```)."
),
},
{"role": "user", "content": markdown_content},
]
)
return response.content
def consolidate_python_and_ts(combined_content: str) -> str:
response = model.invoke(
[
{
"role": "system",
"content": CONSOLIDATION_PROMPT,
"cache_control": {"type": "ephemeral"},
"role": "user",
"content": f"Translate this Python snippet to TypeScript:\n\n{python_snippet}",
},
{"role": "user", "content": combined_content},
]
)
return response.content
# Use a regular expression to search for a TypeScript code block in the response.
pattern = r"```typescript\s*(.*?)\s*```"
match = re.search(pattern, ai_message.content, re.DOTALL)
if match:
# Reconstruct the code block with proper fences.
typescript_code = match.group(1).strip()
return f"```typescript\n{typescript_code}\n```"
else:
raise ValueError("No TypeScript code block found in the model's response.")
def main(file_path: str, translate_only: bool, consolidate_only: bool) -> None:
with open(file_path, "r", encoding="utf-8") as f:
def insert_translations_into_markdown(
markdown: str, typescript_snippets: list[str]
) -> str:
"""Walks through the original markdown content and, after each
Python snippet block, inserts the corresponding translated TypeScript snippet.
It assumes that the ordering of the Python snippets
(from extract_python_snippets) matches the order they appear in the markdown.
"""
output_lines = []
lines = markdown.splitlines(keepends=True)
inside_block = False
snippet_index = 0
for line in lines:
output_lines.append(line)
if not inside_block and opening_pattern.match(line):
# We've encountered the start of a python code block.
inside_block = True
elif inside_block:
if closing_pattern.match(line):
# End of a python snippet block.
inside_block = False
if snippet_index < len(typescript_snippets):
# Insert an extra newline for clarity, then the translated TypeScript snippet.
output_lines.append("\n")
output_lines.append(typescript_snippets[snippet_index])
output_lines.append("\n")
snippet_index += 1
return "".join(output_lines)
def main(file_path: str) -> None:
# Read the markdown file.
with open(file_path, "r") as f:
markdown_content = f.read()
if translate_only:
translated = translate_python_to_ts(markdown_content)
output_path = file_path.replace(".md", ".translated.md")
with open(output_path, "w", encoding="utf-8") as f:
f.write(translated)
print(f"Translated JS/TS version written to: {output_path}")
# 1. Extract all Python snippets.
python_snippets = extract_python_snippets(markdown_content)[:1]
elif consolidate_only:
consolidated = consolidate_python_and_ts(markdown_content)
with open(file_path, "w", encoding="utf-8") as f:
f.write(consolidated)
print(f"Consolidated content written to: {file_path}")
# 2. Translate each Python snippet to TypeScript.
typescript_snippets = []
# Replace with .batch() for faster translation
for python_snippet in _tqdm(python_snippets):
ts_snippet = translate_snippet(python_snippet)
typescript_snippets.append(ts_snippet)
else:
# Default behavior: translate first, then consolidate both
translated = translate_python_to_ts(markdown_content)
combined = f"{markdown_content.strip()}\n\n\n{translated.strip()}"
consolidated = consolidate_python_and_ts(combined)
with open(file_path, "w", encoding="utf-8") as f:
f.write(consolidated)
print(f"Translated and consolidated content written to: {file_path}")
# 3. Insert the TypeScript translations after their respective Python snippets.
updated_markdown = insert_translations_into_markdown(
markdown_content, typescript_snippets
)
# Overwrite the original markdown file with the updated content.
with open(file_path, "w") as f:
f.write(updated_markdown)
if __name__ == "__main__":
parser = argparse.ArgumentParser(
description=(
"Translate Python markdown to TypeScript and/or consolidate "
"Python-JS markdown into one file."
)
description="Translate Python snippets in a markdown file to TypeScript and insert them after each Python snippet."
)
parser.add_argument("file_path", type=str, help="Path to the markdown file.")
parser.add_argument(
"--translate-only",
action="store_true",
help="Only generate the JS translation.",
)
parser.add_argument(
"--consolidate-only",
action="store_true",
help="Only consolidate pre-paired Python and JS content.",
)
args = parser.parse_args()
if args.translate_only and args.consolidate_only:
raise ValueError(
"Cannot use both --translate-only and --consolidate-only at the same time."
)
main(
args.file_path,
translate_only=args.translate_only,
consolidate_only=args.consolidate_only,
)
main(args.file_path)
+5 -6
View File
@@ -3,15 +3,16 @@
import asyncio
import glob
import os
import re
from typing import TypedDict, List, Optional
import pydantic
import re
from pydantic import BaseModel, Field
from langchain_core.rate_limiters import InMemoryRateLimiter
import yaml
from langchain.chat_models import init_chat_model
from langchain_core.rate_limiters import InMemoryRateLimiter
from mkdocs.structure.files import File
from mkdocs.structure.pages import Page
from pydantic import BaseModel, Field
from yaml import SafeLoader
from _scripts.notebook_hooks import _on_page_markdown_with_config
@@ -210,9 +211,7 @@ async def process_nav_items(nav_items: list[NavItem]) -> list[NavItem]:
# Remove any items that start with http:// or https:// looking only for
# local file at this stages.
nav_items = [
item
for item in nav_items
if not item["url"].startswith(("http://", "https://"))
item for item in nav_items if not item["url"].startswith(("http://", "https://"))
]
# Process items in parallel
tasks = [process_single_item(item) for item in nav_items]
-5
View File
@@ -1,5 +0,0 @@
JS_LINK_MAP = {
"langgraph.types.interrupt": "https://langchain-ai.github.io/langgraphjs/reference/functions/langgraph.interrupt-2.html",
"create_react_agent": "https://langchain-ai.github.io/langgraphjs/reference/functions/langgraph_prebuilt.createReactAgent.html",
"langgraph.types.Command": "https://langchain-ai.github.io/langgraphjs/reference/classes/langgraph.Command.html",
}
+42 -160
View File
@@ -3,7 +3,6 @@
Lifecycle events: https://www.mkdocs.org/dev-guide/plugins/#events
"""
import json
import logging
import os
import posixpath
@@ -16,7 +15,6 @@ from mkdocs.structure.files import Files, File
from mkdocs.structure.pages import Page
from _scripts.generate_api_reference_links import update_markdown_with_imports
from _scripts.link_map import JS_LINK_MAP
from _scripts.notebook_convert import convert_notebook
logger = logging.getLogger(__name__)
@@ -35,49 +33,44 @@ REDIRECT_MAP = {
"how-tos/streaming-from-final-node.ipynb": "how-tos/streaming-specific-nodes.ipynb",
"how-tos/streaming-events-from-within-tools-without-langchain.ipynb": "how-tos/streaming-events-from-within-tools.ipynb#example-without-langchain",
# graph-api
"how-tos/state-reducers.ipynb": "how-tos/graph-api.md#define-and-update-state",
"how-tos/sequence.ipynb": "how-tos/graph-api.md#create-a-sequence-of-steps",
"how-tos/branching.ipynb": "how-tos/graph-api.md#create-branches",
"how-tos/recursion-limit.ipynb": "how-tos/graph-api.md#create-and-control-loops",
"how-tos/visualization.ipynb": "how-tos/graph-api.md#visualize-your-graph",
"how-tos/input_output_schema.ipynb": "how-tos/graph-api.md#define-input-and-output-schemas",
"how-tos/pass_private_state.ipynb": "how-tos/graph-api.md#pass-private-state-between-nodes",
"how-tos/state-model.ipynb": "how-tos/graph-api.md#use-pydantic-models-for-graph-state",
"how-tos/map-reduce.ipynb": "how-tos/graph-api.md#map-reduce-and-the-send-api",
"how-tos/command.ipynb": "how-tos/graph-api.md#combine-control-flow-and-state-updates-with-command",
"how-tos/configuration.ipynb": "how-tos/graph-api.md#add-runtime-configuration",
"how-tos/node-retries.ipynb": "how-tos/graph-api.md#add-retry-policies",
"how-tos/return-when-recursion-limit-hits.ipynb": "how-tos/graph-api.md#impose-a-recursion-limit",
"how-tos/async.ipynb": "how-tos/graph-api.md#async",
"how-tos/state-reducers.ipynb": "how-tos/graph-api#define-and-update-state",
"how-tos/sequence.ipynb": "how-tos/graph-api#create-a-sequence-of-steps",
"how-tos/branching.ipynb": "how-tos/graph-api#create-branches",
"how-tos/recursion-limit.ipynb": "how-tos/graph-api#create-and-control-loops",
"how-tos/visualization.ipynb": "how-tos/graph-api#visualize-your-graph",
"how-tos/input_output_schema.ipynb": "how-tos/graph-api#define-input-and-output-schemas",
"how-tos/pass_private_state.ipynb": "how-tos/graph-api#pass-private-state-between-nodes",
"how-tos/state-model.ipynb": "how-tos/graph-api#use-pydantic-models-for-graph-state",
"how-tos/map-reduce.ipynb": "how-tos/graph-api/#map-reduce-and-the-send-api",
"how-tos/command.ipynb": "how-tos/graph-api/#combine-control-flow-and-state-updates-with-command",
"how-tos/configuration.ipynb": "how-tos/graph-api/#add-runtime-configuration",
"how-tos/node-retries.ipynb": "how-tos/graph-api/#add-retry-policies",
"how-tos/return-when-recursion-limit-hits.ipynb": "how-tos/graph-api/#impose-a-recursion-limit",
"how-tos/async.ipynb": "how-tos/graph-api/#async",
# memory how-tos
"how-tos/memory/manage-conversation-history.ipynb": "how-tos/memory/add-memory.md",
"how-tos/memory/delete-messages.ipynb": "how-tos/memory/add-memory.md#delete-messages",
"how-tos/memory/add-summary-conversation-history.ipynb": "how-tos/memory/add-memory.md#summarize-messages",
"how-tos/memory.ipynb": "how-tos/memory/add-memory.md",
"agents/memory.ipynb": "how-tos/memory/add-memory.md",
"how-tos/memory/manage-conversation-history.ipynb": "how-tos/memory.ipynb",
"how-tos/memory/delete-messages.ipynb": "how-tos/memory.ipynb#delete-messages",
"how-tos/memory/add-summary-conversation-history.ipynb": "how-tos/memory.ipynb#summarize-messages",
# subgraph how-tos
"how-tos/subgraph-transform-state.ipynb": "how-tos/subgraph.md#different-state-schemas",
"how-tos/subgraphs-manage-state.ipynb": "how-tos/subgraph.md#add-persistence",
"how-tos/subgraph-transform-state.ipynb": "how-tos/subgraph.ipynb#different-state-schemas",
"how-tos/subgraphs-manage-state.ipynb": "how-tos/subgraph.ipynb#add-persistence",
# persistence how-tos
"how-tos/persistence_postgres.ipynb": "how-tos/memory/add-memory.md#use-in-production",
"how-tos/persistence_mongodb.ipynb": "how-tos/memory/add-memory.md#use-in-production",
"how-tos/persistence_redis.ipynb": "how-tos/memory/add-memory.md#use-in-production",
"how-tos/subgraph-persistence.ipynb": "how-tos/memory/add-memory.md#use-with-subgraphs",
"how-tos/cross-thread-persistence.ipynb": "how-tos/memory/add-memory.md#add-long-term-memory",
"how-tos/persistence_postgres.ipynb": "how-tos/persistence.ipynb#use-in-production",
"how-tos/persistence_mongodb.ipynb": "how-tos/persistence.ipynb#use-in-production",
"how-tos/persistence_redis.ipynb": "how-tos/persistence.ipynb#use-in-production",
"how-tos/subgraph-persistence.ipynb": "how-tos/persistence.ipynb#use-with-subgraphs",
"how-tos/cross-thread-persistence.ipynb": "how-tos/persistence.ipynb#add-long-term-memory",
"cloud/how-tos/copy_threads": "cloud/how-tos/use_threads",
"cloud/how-tos/check-thread-status": "cloud/how-tos/use_threads",
"cloud/concepts/threads.md": "concepts/persistence.md#threads",
"how-tos/persistence.ipynb": "how-tos/memory/add-memory.md",
# tool calling how-tos
"how-tos/tool-calling-errors.ipynb": "how-tos/tool-calling.ipynb#handle-errors",
"how-tos/pass-config-to-tools.ipynb": "how-tos/tool-calling.ipynb#access-config",
"how-tos/pass-run-time-values-to-tools.ipynb": "how-tos/tool-calling.ipynb#read-state",
"how-tos/update-state-from-tools.ipynb": "how-tos/tool-calling.ipynb#update-state",
"agents/tools.md": "how-tos/tool-calling.md",
# multi-agent how-tos
"how-tos/agent-handoffs.ipynb": "how-tos/multi_agent.md#handoffs",
"how-tos/multi-agent-network.ipynb": "how-tos/multi_agent.md#use-in-a-multi-agent-system",
"how-tos/multi-agent-multi-turn-convo.ipynb": "how-tos/multi_agent.md#multi-turn-conversation",
"how-tos/agent-handoffs.ipynb": "how-tos/multi_agent.ipynb#handoffs",
"how-tos/multi-agent-network.ipynb": "how-tos/multi_agent.ipynb#use-in-a-multi-agent-system",
"how-tos/multi-agent-multi-turn-convo.ipynb": "how-tos/multi_agent.ipynb#multi-turn-conversation",
# cloud redirects
"cloud/index.md": "index.md",
"cloud/how-tos/index.md": "concepts/langgraph_platform",
@@ -96,11 +89,16 @@ REDIRECT_MAP = {
"cloud/how-tos/stream_multiple.md": "cloud/how-tos/streaming.md#stream-multiple-modes",
"cloud/concepts/streaming.md": "concepts/streaming.md",
"agents/streaming.md": "how-tos/streaming.md",
# prebuilt redirects
# prebuit redirects
"how-tos/create-react-agent.ipynb": "agents/agents.md#basic-configuration",
"how-tos/create-react-agent-memory.ipynb": "agents/memory.md",
"how-tos/create-react-agent-system-prompt.ipynb": "agents/context.md#prompts",
"how-tos/create-react-agent-hitl.ipynb": "agents/human-in-the-loop.md",
"how-tos/create-react-agent-structured-output.ipynb": "agents/agents.md#structured-output",
# Time-travel
"how-tos/human_in_the_loop/edit-graph-state.ipynb": "how-tos/human_in_the_loop/time-travel.ipynb",
# breakpoints
"how-tos/human_in_the_loop/dynamic_breakpoints.ipynb": "how-tos/human_in_the_loop/breakpoints.ipynb",
# misc
"prebuilt.md": "agents/prebuilt.md",
"reference/prebuilt.md": "reference/agents.md",
@@ -109,7 +107,6 @@ REDIRECT_MAP = {
"concepts/v0-human-in-the-loop.md": "concepts/human-in-the-loop.md",
"how-tos/index.md": "index.md",
"tutorials/introduction.ipynb": "concepts/why-langgraph.md",
"agents/deployment.md": "tutorials/langgraph-platform/local-server.md",
# deployment redirects
"how-tos/deploy-self-hosted.md": "cloud/deployment/self_hosted_data_plane.md",
"concepts/self_hosted.md": "concepts/langgraph_self_hosted_data_plane.md",
@@ -117,16 +114,6 @@ REDIRECT_MAP = {
# assistant redirects
"cloud/how-tos/assistant_versioning.md": "cloud/how-tos/configuration_cloud.md",
"cloud/concepts/runs.md": "concepts/assistants.md#execution",
# hitl redirects
"how-tos/wait-user-input-functional.ipynb": "how-tos/use-functional-api.md",
"how-tos/review-tool-calls-functional.ipynb": "how-tos/use-functional-api.md",
"how-tos/create-react-agent-hitl.ipynb": "how-tos/human_in_the_loop/add-human-in-the-loop.md",
"agents/human-in-the-loop.md": "how-tos/human_in_the_loop/add-human-in-the-loop.md",
"how-tos/human_in_the_loop/dynamic_breakpoints.ipynb": "how-tos/human_in_the_loop/breakpoints.md",
"concepts/breakpoints.md": "concepts/human_in_the_loop.md",
"how-tos/human_in_the_loop/breakpoints.md": "how-tos/human_in_the_loop/add-human-in-the-loop.md",
"cloud/how-tos/human_in_the_loop_breakpoint.md": "cloud/how-tos/add-human-in-the-loop.md",
"how-tos/human_in_the_loop/edit-graph-state.ipynb": "how-tos/human_in_the_loop/time-travel.md",
}
@@ -176,62 +163,6 @@ def _add_path_to_code_blocks(markdown: str, page: Page) -> str:
return code_block_pattern.sub(replace_code_block_header, markdown)
def _resolve_cross_references(md_text: str, link_map: dict[str, str]) -> str:
"""Replace [title][identifier] with [title](url) using language-specific link_map.
Args:
md_text: The markdown text to process.
link_map: mapping of identifier to URL.
Returns:
The processed markdown text with cross-references resolved.
"""
# Pattern to match [title][identifier]
pattern = re.compile(r"\[([^\]]+)\]\[([^\]]+)\]")
def replace_reference(match: re.Match) -> str:
"""Replace the matched reference with the corresponding URL."""
title, identifier = match.group(1), match.group(2)
url = link_map.get(identifier)
if url:
return f"[{title}]({url})"
else:
# Leave it unchanged if not found
return match.group(0)
return pattern.sub(replace_reference, md_text)
def _apply_conditional_rendering(md_text: str, target_language: str) -> str:
if target_language not in {"python", "js"}:
raise ValueError("target_language must be 'python' or 'js'")
pattern = re.compile(
r"(?P<indent>[ \t]*):::(?P<language>\w+)\s*\n"
r"(?P<content>((?:.*\n)*?))" # Capture the content inside the block
r"(?P=indent):::" # Match closing with the same indentation
)
def replace_conditional_blocks(match: re.Match) -> str:
"""Keep active conditionals."""
language = match.group("language")
content = match.group("content")
if language not in {"python", "js"}:
# If the language is not supported, return the original block
return match.group(0)
if language == target_language:
return content
# If the language does not match, return an empty string
return ""
processed = pattern.sub(replace_conditional_blocks, md_text)
return processed
def _highlight_code_blocks(markdown: str) -> str:
"""Find code blocks with highlight comments and add hl_lines attribute.
@@ -331,20 +262,6 @@ def _on_page_markdown_with_config(
# Apply highlight comments to code blocks
markdown = _highlight_code_blocks(markdown)
# Apply conditional rendering for code blocks
target_language = kwargs.get("target_language", "python")
markdown = _apply_conditional_rendering(markdown, target_language)
if target_language == "js":
markdown = _resolve_cross_references(markdown, JS_LINK_MAP)
elif target_language == "python":
# Via a dedicated plugin
pass
else:
raise ValueError(
f"Unsupported target language: {target_language}. "
"Supported languages are 'python' and 'js'."
)
# Add file path as an attribute to code blocks that are executable.
# This file path is used to associate fixtures with the executable code
# which can be used in CI to test the docs without making network requests.
@@ -358,16 +275,12 @@ def _on_page_markdown_with_config(
def on_page_markdown(markdown: str, page: Page, **kwargs: Dict[str, Any]):
finalized_markdown = (
_on_page_markdown_with_config(
markdown,
page,
add_api_references=True,
**kwargs,
)
return _on_page_markdown_with_config(
markdown,
page,
add_api_references=True,
**kwargs,
)
page.meta["original_markdown"] = finalized_markdown
return finalized_markdown
# redirects
@@ -437,51 +350,20 @@ height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
else:
return html # fallback if no <body> found
def _inject_markdown_into_html(html: str, page: Page) -> str:
"""Inject the original markdown content into the HTML page as JSON."""
original_markdown = page.meta.get("original_markdown", "")
if not original_markdown:
return html
markdown_data = {
"markdown": original_markdown,
"title": page.title or "Page Content",
"url": page.url or "",
}
# Properly escape the JSON for HTML
json_content = json.dumps(markdown_data, ensure_ascii=False)
json_content = (
json_content.replace("</", "\\u003c/")
.replace("<script", "\\u003cscript")
.replace("</script", "\\u003c/script")
)
script_content = (
f'<script id="page-markdown-content" '
f'type="application/json">{json_content}</script>'
)
# Insert before </head> if it exists, otherwise before </body>
if "</head>" not in html:
raise ValueError(
"HTML does not contain </head> tag. Cannot inject markdown content."
)
return html.replace("</head>", f"{script_content}</head>")
def on_post_page(html: str, page: Page, config: MkDocsConfig) -> str:
def on_post_page(output: str, page: Page, config: MkDocsConfig) -> str:
"""Inject Google Tag Manager noscript tag immediately after <body>.
Args:
html: The HTML output of the page.
output: The HTML output of the page.
page: The page instance.
config: The MkDocs configuration object.
Returns:
modified HTML output with GTM code injected.
"""
html = _inject_markdown_into_html(html, page)
return _inject_gtm(html)
return _inject_gtm(output)
# Create HTML files for redirects after site dir has been built
def on_post_build(config):
-11
View File
@@ -1,11 +0,0 @@
# Additional resources
This section contains additional resources for LangGraph.
- [Community agents](../agents/prebuilt.md): A collection of prebuilt libraries that you can use in your LangGraph applications.
- [LangGraph Academy](https://academy.langchain.com/courses/intro-to-langgraph): A collection of courses that teach you how to use LangGraph.
- [Case studies](../adopters.md): A collection of case studies that show how LangGraph is used in production.
- [FAQ](../concepts/faq.md): A collection of frequently asked questions about LangGraph.
- [llms.txt](../llms-txt-overview.md): A list of documentation files in the `llms.txt` format that allow LLMs and agents to access our documentation.
- [LangChain Forum](https://forum.langchain.com/): A place to ask questions and get help from other LangGraph users.
- [Troubleshooting](../troubleshooting/errors/index.md): A collection of troubleshooting guides for common issues.
+6 -23
View File
@@ -8,41 +8,24 @@ This list of companies using LangGraph and their success stories is compiled fro
| [AirTop](https://www.airtop.ai/) | Software & Technology (GenAI Native) | Browser automation for AI agents | [Case study, 2024](https://blog.langchain.dev/customers-airtop/) |
| [AppFolio](https://www.appfolio.com/) | Real Estate | Copilot for domain-specific task | [Case study, 2024](https://blog.langchain.dev/customers-appfolio/) |
| [Athena Intelligence](https://www.athenaintel.com/) | Software & Technology (GenAI Native) | Research & summarization | [Case study, 2024](https://blog.langchain.dev/customers-athena-intelligence/) |
| [BlackRock](https://www.blackrock.com/) | Financial Services | Copilot for domain-specific task | [Interrupt talk, 2025](https://youtu.be/oyqeCHFM5U4?feature=shared) |
| [Captide](https://www.captide.co/) | Software & Technology (GenAI Native) | Data extraction | [Case study, 2025](https://blog.langchain.dev/how-captide-is-redefining-equity-research-with-agentic-workflows-built-on-langgraph-and-langsmith/) |
| [Cisco CX](https://www.cisco.com/site/us/en/services/modern-data-center/index.html?CCID=cc005911&DTID=eivtotr001480&OID=srwsas032775) | Software & Technology | Customer support | [Interrupt Talk, 2025](https://youtu.be/gPhyPRtIMn0?feature=shared) |
| [Cisco Outshift](https://outshift.cisco.com/) | Software & Technology | DevOps | [Video story, 2025](https://www.youtube.com/watch?v=htcb-vGR_x0); [Case study, 2025](https://blog.langchain.com/cisco-outshift/); [Blog post, 2025](https://outshift.cisco.com/blog/build-react-agent-application-for-devops-tasks-using-rest-apis) |
| [Cisco TAC](https://www.cisco.com/c/en/us/support/index.html) | Software & Technology | Customer support | [Video story, 2025](https://youtu.be/EAj0HBDGqaE?feature=shared) |
| [City of Hope](https://www.cityofhope.org/) | Non-profit | Copilot for domain-specific task | [Video story, 2025](https://youtu.be/9ABwtK2gIZU?feature=shared) |
| [Cisco Outshift](https://outshift.cisco.com/) | Software & Technology | DevOps | [Blog post, 2025](https://outshift.cisco.com/blog/build-react-agent-application-for-devops-tasks-using-rest-apis) |
| [C.H. Robinson](https://www.chrobinson.com/en-us/) | Logistics | Automation | [Case study, 2025](https://blog.langchain.dev/customers-chrobinson/) |
| [Definely](https://www.definely.com/) | Legal | Copilot for domain-specific task | [Case study, 2025](https://blog.langchain.com/customers-definely/) |
| [Docent Pro](https://docentpro.com/) | Travel | GenAI embedded product experiences | [Case study, 2025](https://blog.langchain.com/customers-docentpro/) |
| [Elastic](https://www.elastic.co/) | Software & Technology | Copilot for domain-specific task | [Blog post, 2025](https://www.elastic.co/blog/elastic-security-generative-ai-features) |
| [Exa](https://exa.ai/) | Software & Technology (GenAI Native) | Search | [Case study, 2025](https://blog.langchain.com/exa/) |
| [GitLab](https://about.gitlab.com/) | Software & Technology | Code generation | [Duo workflow docs](https://handbook.gitlab.com/handbook/engineering/architecture/design-documents/duo_workflow/) |
| [Harmonic](https://harmonic.ai/) | Software & Technology | Search | [Case study, 2025](https://blog.langchain.com/customers-harmonic/) |
| [Inconvo](https://inconvo.ai/?ref=blog.langchain.dev) | Software & Technology | Code generation | [Case study, 2025](https://blog.langchain.dev/customers-inconvo/) |
| [Infor](https://infor.com/) | Software & Technology | GenAI embedded product experiences; customer support; copilot | [Case study, 2025](https://blog.langchain.dev/customers-infor/) |
| [J.P. Morgan](https://www.jpmorganchase.com/) | Financial Services | Copilot for domain-specific task | [Interrupt talk, 2025](https://youtu.be/yMalr0jiOAc?feature=shared) |
| [Klarna](https://www.klarna.com/) | Fintech | Copilot for domain-specific task | [Case study, 2025](https://blog.langchain.dev/customers-klarna/) |
| [Komodo Health](https://www.komodohealth.com/) | Healthcare | Copilot for domain-specific task | [Blog post](https://www.komodohealth.com/perspectives/new-gen-ai-assistant-empowers-the-enterprise/) |
| [LinkedIn](https://www.linkedin.com/) | Social Media | Code generation; Search & discovery | [Interrupt talk, 2025](https://youtu.be/NmblVxyBhi8?feature=shared); [Blog post, 2025](https://www.linkedin.com/blog/engineering/ai/practical-text-to-sql-for-data-analytics); [Blog post, 2024](https://www.linkedin.com/blog/engineering/generative-ai/behind-the-platform-the-journey-to-create-the-linkedin-genai-application-tech-stack) |
| [LinkedIn](https://www.linkedin.com/) | Social Media | Code generation; Search & discovery | [Blog post, 2025](https://www.linkedin.com/blog/engineering/ai/practical-text-to-sql-for-data-analytics); [Blog post, 2024](https://www.linkedin.com/blog/engineering/generative-ai/behind-the-platform-the-journey-to-create-the-linkedin-genai-application-tech-stack) |
| [Minimal](https://gominimal.ai/) | E-commerce | Customer support | [Case study, 2025](https://blog.langchain.dev/how-minimal-built-a-multi-agent-customer-support-system-with-langgraph-langsmith/) |
| [Modern Treasury](https://www.moderntreasury.com/) | Fintech | GenAI embedded product experiences | [Video story, 2025](https://youtu.be/AwAiffXqaCU?feature=shared) |
| [Monday](https://monday.com/) | Software & Technology | GenAI embedded product experiences | [Interrupt talk, 2025](https://blog.langchain.dev/how-minimal-built-a-multi-agent-customer-support-system-with-langgraph-langsmith/) |
| [Morningstar](https://www.morningstar.com/) | Financial Services | Research & summarization | [Video story, 2025](https://youtu.be/6LidoFXCJPs?feature=shared) |
| [OpenRecovery](https://www.openrecovery.com/) | Healthcare | Copilot for domain-specific task | [Case study, 2024](https://blog.langchain.dev/customers-openrecovery/) |
| [Pigment](https://www.pigment.com/) | Fintech | GenAI embedded product experiences | [Video story, 2025](https://youtu.be/5JVSO2KYOmE?feature=shared) |
| [Prosper](https://www.prosper.com/) | Fintech | Customer support | [Video story, 2025](https://youtu.be/9RFNOYtkwsc?feature=shared) |
| [Qodo](https://www.qodo.ai/) | Software & Technology (GenAI Native) | Code generation | [Blog post, 2025](https://www.qodo.ai/blog/why-we-chose-langgraph-to-build-our-coding-agent/) |
| [Rakuten](https://www.rakuten.com/) | E-commerce / Fintech | Copilot for domain-specific task | [Video story, 2025](https://youtu.be/gD1LIjCkuA8?feature=shared); [Blog post, 2025](https://rakuten.today/blog/from-ai-hype-to-real-world-tools-rakuten-teams-up-with-langchain.html) |
| [Rakuten](https://www.rakuten.com/) | E-commerce / Fintech | Copilot for domain-specific task | [Blog post, 2025](https://rakuten.today/blog/from-ai-hype-to-real-world-tools-rakuten-teams-up-with-langchain.html) |
| [Replit](https://replit.com/) | Software & Technology | Code generation | [Blog post, 2024](https://blog.langchain.dev/customers-replit/); [Breakout agent story, 2024](https://www.langchain.com/breakoutagents/replit); [Fireside chat video, 2024](https://www.youtube.com/watch?v=ViykMqljjxU) |
| [Rexera](https://www.rexera.com/) | Real Estate (GenAI Native) | Copilot for domain-specific task | [Case study, 2024](https://blog.langchain.dev/customers-rexera/) |
| [Abu Dhabi Government](https://www.tamm.abudhabi/) | Government | Search | [Case study, 2025](https://blog.langchain.com/customers-abu-dhabi-government/) |
| [Tradestack](https://www.tradestack.uk/) | Software & Technology (GenAI Native) | Copilot for domain-specific task | [Case study, 2024](https://blog.langchain.dev/customers-tradestack/) |
| [Uber](https://www.uber.com/) | Transportation | Developer productivity; Code generation | [Interrupt talk, 2025](https://youtu.be/Bugs0dVcNI8?feature=shared); [Presentation, 2024](https://dpe.org/sessions/ty-smith-adam-huda/this-year-in-ubers-ai-driven-developer-productivity-revolution/); [Video, 2024](https://www.youtube.com/watch?v=8rkA5vWUE4Y) |
| [Unify](https://www.unifygtm.com/) | Software & Technology (GenAI Native) | Copilot for domain-specific task | [Interrupt talk, 2025](https://youtu.be/pKk-LfhujwI?feature=shared); [Blog post, 2024](https://blog.langchain.dev/unify-launches-agents-for-account-qualification-using-langgraph-and-langsmith/) |
| [Vizient](https://www.vizientinc.com/) | Healthcare | Copilot for domain-specific task | [Video story, 2025](https://www.youtube.com/watch?v=vrjJ6NuyTWA); [Case study, 2025](https://blog.langchain.dev/p/3d2cd58c-13a5-4df9-bd84-7d54ed0ed82c/) |
| [Uber](https://www.uber.com/) | Transportation | Developer productivity; Code generation | [Presentation, 2024](https://dpe.org/sessions/ty-smith-adam-huda/this-year-in-ubers-ai-driven-developer-productivity-revolution/); [Video, 2024](https://www.youtube.com/watch?v=8rkA5vWUE4Y) |
| [Unify](https://www.unifygtm.com/) | Software & Technology (GenAI Native) | Copilot for domain-specific task | [Blog post, 2024](https://blog.langchain.dev/unify-launches-agents-for-account-qualification-using-langgraph-and-langsmith/) |
| [Vizient](https://www.vizientinc.com/) | Healthcare | Copilot for domain-specific task | [Case study, 2025](https://blog.langchain.dev/p/3d2cd58c-13a5-4df9-bd84-7d54ed0ed82c/) |
| [Vodafone](https://www.vodafone.com/) | Telecommunications | Code generation; internal search | [Case study, 2025](https://blog.langchain.dev/customers-vodafone/) |
| [WebToon](https://www.webtoons.com/en/) | Media & Entertainment | Data extraction | [Case study, 2025](https://blog.langchain.com/customers-webtoon/) |
| [11x](https://www.11x.ai/) | Software & Technology (GenAI Native) | Research & outreach | [Interrupt talk, 2025](https://youtu.be/fegwPmaAPQk?feature=shared) |
+3 -3
View File
@@ -52,7 +52,7 @@ agent.invoke(
)
```
1. Define a tool for the agent to use. Tools can be defined as vanilla Python functions. For more advanced tool usage and customization, check the [tools](../how-tos/tool-calling.md) page.
1. Define a tool for the agent to use. Tools can be defined as vanilla Python functions. For more advanced tool usage and customization, check the [tools](./tools.md) page.
2. Provide a language model for the agent to use. To learn more about configuring language models for the agents, check the [models](./models.md) page.
3. Provide a list of tools for the model to use.
4. Provide a system prompt (instructions) to the language model used by the agent.
@@ -180,14 +180,14 @@ ny_response = agent.invoke(
)
```
1. `checkpointer` allows the agent to store its state at every step in the tool calling loop. This enables [short-term memory](../how-tos/memory/add-memory.md#add-short-term-memory) and [human-in-the-loop](../concepts/human_in_the_loop.md) capabilities.
1. `checkpointer` allows the agent to store its state at every step in the tool calling loop. This enables [short-term memory](./memory.md#short-term-memory) and [human-in-the-loop](./human-in-the-loop.md) capabilities.
2. Pass configuration with `thread_id` to be able to resume the same conversation on future agent invocations.
When you enable the checkpointer, it stores agent state at every step in the provided checkpointer database (or in memory, if using `InMemorySaver`).
Note that in the above example, when the agent is invoked the second time with the same `thread_id`, the original message history from the first conversation is automatically included, together with the new user input.
For more information, see [Memory](../how-tos/memory/add-memory.md).
For more information, see [Memory](./memory.md).
## 6. Configure structured output
+154 -112
View File
@@ -1,8 +1,17 @@
---
search:
boost: 2
tags:
- agent
hide:
- tags
---
# Context
**Context engineering** is the practice of building dynamic systems that provide the right information and tools, in the right format, so that a language model can plausibly accomplish a task.
Agents often require more than a list of messages to function effectively. They need **context**.
Context includes *any* data outside the message list that can shape behavior. This can be:
Context includes *any* data outside the message list that can shape agent behavior or tool execution. This can be:
- Information passed at runtime, like a `user_id` or API credentials.
- Internal state updated during a multi-step reasoning process.
@@ -12,108 +21,79 @@ LangGraph provides **three** primary ways to supply context:
| Type | Description | Mutable? | Lifetime |
|------------------------------------------------------------------------------|-----------------------------------------------|----------|-------------------------|
| [**Runtime Context**](#runtime-context) | data passed at the start of a run | ❌ | per run |
| [**Short-term memory (State)**](#short-term-memory-mutable-context) | dynamic data that can change during execution | ✅ | per run or conversation |
| [**Long-term memory (Store)**](#long-term-memory-cross-conversation-context) | data that can be shared between conversations | ✅ | across conversations |
| [**Config**](#config-static-context) | data passed at the start of a run | ❌ | per run |
| [**State**](#state-mutable-context) | dynamic data that can change during execution | ✅ | per run or conversation |
| [**Long-term Memory (Store)**](#long-term-memory-cross-conversation-context) | data that can be shared between conversations | ✅ | across conversations |
### Runtime Context
You can use context to:
!!! note "`config['configurable']` -> `runtime.context`"
- Adjust the system prompt the model sees
- Feed tools with necessary inputs
- Track facts during an ongoing conversation
In LangGraph < v1.0, static runtime context was passed via the `config['configurable']` key, paired with a `config_schema` argument
to `StateGraph` or `Pregel`. This is now deprecated and will be removed in v2.0.
## Providing Runtime Context
As of LangGraph v1.0, the Runtime object is recommended to access static context and runtime-specific information like the store and stream writer.
Use this when you need to inject data into an agent at runtime.
Runtime context is for immutable data like user metadata or API keys. Use this when you have values that don't change mid-run.
### Config (static context)
Specify static context via the `context` argument to `invoke` / `stream`, which is reserved for this purpose:
Config is for immutable data like user metadata or API keys. Use
when you have values that don't change mid-run.
Specify configuration using a key called **"configurable"** which is reserved
for this purpose:
```python
@dataclass
class ContextSchema:
user_name: str
graph.invoke( # (1)!
{"messages": [{"role": "user", "content": "hi!"}]}, # (2)!
agent.invoke(
{"messages": [{"role": "user", "content": "hi!"}]},
# highlight-next-line
context={"user_name": "John Smith"} # (3)!
config={"configurable": {"user_id": "user_123"}}
)
```
1. This is the invocation of the agent or graph. The `invoke` method runs the underlying graph with the provided input.
2. This example uses messages as an input, which is common, but your application may use different input structures.
3. This is where you pass the runtime data. The `context` parameter allows you to provide additional dependencies that the agent can use during its execution.
### State (mutable context)
=== "Agent prompt"
```python
from langchain_core.messages import AnyMessage
from langgraph.runtime import get_runtime
from langgraph.prebuilt.chat_agent_executor import AgentState
from langgraph.prebuilt import create_react_agent
State acts as short-term memory during a run. It holds dynamic data that can evolve during execution, such as values derived from tools or LLM outputs.
```python
class CustomState(AgentState):
# highlight-next-line
def prompt(state: AgentState) -> list[AnyMessage]:
runtime = get_runtime(ContextSchema)
system_msg = f"You are a helpful assistant. Address the user as {runtime.context.user_name}."
return [{"role": "system", "content": system_msg}] + state["messages"]
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_weather],
prompt=prompt,
context_schema=ContextSchema
)
agent.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
# highlight-next-line
context={"user_name": "John Smith"}
)
```
* See [Agents](../agents/agents.md) for details.
=== "Workflow node"
```python
from langgraph.runtime import Runtime
user_name: str
agent = create_react_agent(
# Other agent parameters...
# highlight-next-line
def node(state: State, config: Runtime[ContextSchema]):
user_name = runtime.context.user_name
...
```
state_schema=CustomState,
)
* See [the Graph API](https://langchain-ai.github.io/langgraph/how-tos/graph-api/#add-runtime-configuration) for details.
agent.invoke({
"messages": "hi!",
"user_name": "Jane"
})
```
=== "In a tool"
!!! tip "Turning on memory"
```python
from langgraph.runtime import get_runtime
Please see the [memory guide](./memory.md) for more details on how to enable memory. This is a powerful feature that allows you to persist the agent's state across multiple invocations.
Otherwise, the state is scoped only to a single agent run.
@tool
# highlight-next-line
def get_user_email() -> str:
"""Retrieve user information based on user ID."""
# simulate fetching user info from a database
runtime = get_runtime(ContextSchema)
email = get_user_email_from_db(runtime.context.user_name)
return email
```
See the [tool calling guide](../how-tos/tool-calling.md#configuration) for details.
### Short-term memory (mutable context)
### Long-Term Memory (cross-conversation context)
State acts as [short-term memory](../concepts/memory.md) during a run. It holds dynamic data that can evolve during execution, such as values derived from tools or LLM outputs.
For context that spans *across* conversations or sessions, LangGraph allows access to **long-term memory** via a `store`. This can be used to read or update persistent facts (e.g., user profiles, preferences, prior interactions). For more, see the [Memory guide](./memory.md).
=== "In an agent"
## Customizing Prompts with Context { #prompts }
Example shows how to incorporate state into an agent **prompt**.
Prompts define how the agent behaves. To incorporate runtime context, you can dynamically generate prompts based on the agent's state or config.
State can also be accessed by the agent's **tools**, which can read or update the state as needed. See [tool calling guide](../how-tos/tool-calling.md#short-term-memory) for details.
Common use cases:
- Personalization
- Role or goal customization
- Conditional behavior (e.g., user is admin)
=== "Using config"
```python
from langchain_core.messages import AnyMessage
@@ -121,14 +101,47 @@ State acts as [short-term memory](../concepts/memory.md) during a run. It holds
from langgraph.prebuilt import create_react_agent
from langgraph.prebuilt.chat_agent_executor import AgentState
# highlight-next-line
class CustomState(AgentState): # (1)!
def prompt(
state: AgentState,
# highlight-next-line
config: RunnableConfig,
) -> list[AnyMessage]:
# highlight-next-line
user_name = config["configurable"].get("user_name")
system_msg = f"You are a helpful assistant. User's name is {user_name}"
return [{"role": "system", "content": system_msg}] + state["messages"]
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_weather],
# highlight-next-line
prompt=prompt
)
agent.invoke(
...,
# highlight-next-line
config={"configurable": {"user_name": "John Smith"}}
)
```
=== "Using state"
```python
from langchain_core.messages import AnyMessage
from langchain_core.runnables import RunnableConfig
from langgraph.prebuilt import create_react_agent
from langgraph.prebuilt.chat_agent_executor import AgentState
class CustomState(AgentState):
# highlight-next-line
user_name: str
def prompt(
# highlight-next-line
state: CustomState
) -> list[AnyMessage]:
# highlight-next-line
user_name = state["user_name"]
system_msg = f"You are a helpful assistant. User's name is {user_name}"
return [{"role": "system", "content": system_msg}] + state["messages"]
@@ -137,58 +150,87 @@ State acts as [short-term memory](../concepts/memory.md) during a run. It holds
model="anthropic:claude-3-7-sonnet-latest",
tools=[...],
# highlight-next-line
state_schema=CustomState, # (2)!
state_schema=CustomState,
# highlight-next-line
prompt=prompt
)
agent.invoke({
"messages": "hi!",
# highlight-next-line
"user_name": "John Smith"
})
```
1. Define a custom state schema that extends `AgentState` or `MessagesState`.
2. Pass the custom state schema to the agent. This allows the agent to access and modify the state during execution.
## Accessing Context in Tools { #tools }
Tools can access context through special parameter **annotations**.
* Use `RunnableConfig` for config access
* Use `Annotated[StateSchema, InjectedState]` for agent state
=== "In a workflow"
!!! tip
These annotations prevent LLMs from attempting to fill in the values. These parameters will be **hidden** from the LLM.
=== "Using config"
```python
from typing_extensions import TypedDict
from langchain_core.messages import AnyMessage
from langgraph.graph import StateGraph
def get_user_info(
# highlight-next-line
config: RunnableConfig,
) -> str:
"""Look up user info."""
# highlight-next-line
user_id = config["configurable"].get("user_id")
return "User is John Smith" if user_id == "user_123" else "Unknown user"
# highlight-next-line
class CustomState(TypedDict): # (1)!
messages: list[AnyMessage]
extra_field: int
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_user_info],
)
# highlight-next-line
def node(state: CustomState): # (2)!
messages = state["messages"]
...
return { # (3)!
# highlight-next-line
"extra_field": state["extra_field"] + 1
}
builder = StateGraph(State)
builder.add_node(node)
builder.set_entry_point("node")
graph = builder.compile()
agent.invoke(
{"messages": [{"role": "user", "content": "look up user information"}]},
# highlight-next-line
config={"configurable": {"user_id": "user_123"}}
)
```
1. Define a custom state
2. Access the state in any node or tool
3. The Graph API is designed to work as easily as possible with state. The return value of a node represents a requested update to the state.
=== "Using State"
!!! tip "Turning on memory"
```python
from typing import Annotated
from langgraph.prebuilt import InjectedState
Please see the [memory guide](../how-tos/memory/add-memory.md) for more details on how to enable memory. This is a powerful feature that allows you to persist the agent's state across multiple invocations. Otherwise, the state is scoped only to a single run.
class CustomState(AgentState):
# highlight-next-line
user_id: str
### Long-term memory (cross-conversation context)
def get_user_info(
# highlight-next-line
state: Annotated[CustomState, InjectedState]
) -> str:
"""Look up user info."""
# highlight-next-line
user_id = state["user_id"]
return "User is John Smith" if user_id == "user_123" else "Unknown user"
For context that spans *across* conversations or sessions, LangGraph allows access to **long-term memory** via a `store`. This can be used to read or update persistent facts (e.g., user profiles, preferences, prior interactions).
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_user_info],
# highlight-next-line
state_schema=CustomState,
)
For more information, see the [Memory guide](../how-tos/memory/add-memory.md).
agent.invoke({
"messages": "look up user information",
# highlight-next-line
"user_id": "user_123"
})
```
### Update Context from Tools
Tools can update agent's context (state and long-term memory) during execution. This is useful for persisting intermediate results or making information accessible to subsequent tools or prompts. See [Memory](./memory.md#read-short-term) guide for more information.
+92
View File
@@ -0,0 +1,92 @@
---
search:
boost: 2
tags:
- agent
hide:
- tags
---
# Deployment
To deploy your LangGraph agent, create and configure a LangGraph app. This setup supports both local development and production deployments.
Features:
* 🖥️ Local server for development
* 🧩 Studio Web UI for visual debugging
* ☁️ Cloud and 🔧 self-hosted deployment options
* 📊 LangSmith integration for tracing and observability
!!! info "Requirements"
- ✅ You **must** have a [LangSmith account](https://www.langchain.com/langsmith). You can sign up for **free** and get started with the free tier.
## Create a LangGraph app
```bash
pip install -U "langgraph-cli[inmem]"
langgraph new path/to/your/app --template new-langgraph-project-python
```
This will create an empty LangGraph project. You can modify it by replacing the code in `src/agent/graph.py` with your agent code. For example:
```python
from langgraph.prebuilt import create_react_agent
def get_weather(city: str) -> str:
"""Get weather for a given city."""
return f"It's always sunny in {city}!"
graph = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_weather],
prompt="You are a helpful assistant"
)
```
### Install dependencies
In the root of your new LangGraph app, install the dependencies in `edit` mode so your local changes are used by the server:
```shell
pip install -e .
```
### Create an `.env` file
You will find a `.env.example` in the root of your new LangGraph app. Create
a `.env` file in the root of your new LangGraph app and copy the contents of the `.env.example` file into it, filling in the necessary API keys:
```bash
LANGSMITH_API_KEY=lsv2...
ANTHROPIC_API_KEY=sk-
```
## Launch LangGraph server locally
```shell
langgraph dev
```
This will start up the LangGraph API server locally. If this runs successfully, you should see something like:
> Ready!
>
> - API: [http://localhost:2024](http://localhost:2024/)
>
> - Docs: http://localhost:2024/docs
>
> - LangGraph Studio Web UI: https://smith.langchain.com/studio/?baseUrl=http://127.0.0.1:2024
See this [tutorial](https://langchain-ai.github.io/langgraph/tutorials/langgraph-platform/local-server/) to learn more about running LangGraph app locally.
## LangGraph Studio Web UI
LangGraph Studio Web is a specialized UI that you can connect to LangGraph API server to enable visualization, interaction, and debugging of your application locally. Test your graph in the LangGraph Studio Web UI by visiting the URL provided in the output of the `langgraph dev` command.
> - LangGraph Studio Web UI: https://smith.langchain.com/studio/?baseUrl=http://127.0.0.1:2024
## Deployment
Once your LangGraph app is running locally, you can deploy it using LangGraph Platform. Refer to the [deployment options guide](../concepts/deployment_options.md) for detailed instructions on all supported deployment models.
+1 -1
View File
@@ -15,7 +15,7 @@ To evaluate your agent's performance you can use `LangSmith` [evaluations](https
def evaluator(*, outputs: dict, reference_outputs: dict):
# compare agent outputs against reference outputs
output_messages = outputs["messages"]
reference_messages = reference_outputs["messages"]
reference_messages = reference["messages"]
score = compare_messages(output_messages, reference_messages)
return {"key": "evaluator_score", "score": score}
```
+238
View File
@@ -0,0 +1,238 @@
---
search:
boost: 2
tags:
- human-in-the-loop
- hil
- agent
hide:
- tags
---
# Human-in-the-loop
To review, edit and approve tool calls in an agent you can use LangGraph's built-in [Human-In-the-Loop (HIL)](../concepts/human_in_the_loop.md) features, specifically the [`interrupt()`][langgraph.types.interrupt] primitive.
LangGraph allows you to pause execution **indefinitely** — for minutes, hours, or even days—until human input is received.
This is possible because the agent state is **checkpointed into a database**, which allows the system to persist execution context and later resume the workflow, continuing from where it left off.
For a deeper dive into the **human-in-the-loop** concept, see the [concept guide](../concepts/human_in_the_loop.md).
<figure markdown="1">
![image](../concepts/img/human_in_the_loop/tool-call-review.png){: style="max-height:400px"}
<figcaption>
A human can review and edit the output from the agent before proceeding. This is particularly critical in applications where the tool calls requested may be sensitive or require human oversight.
</figcaption>
</figure>
## Review tool calls
To add a human approval step to a tool:
1. Use `interrupt()` in the tool to pause execution.
2. Resume with a `Command(resume=...)` to continue based on human input.
```python
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.types import interrupt
from langgraph.prebuilt import create_react_agent
# An example of a sensitive tool that requires human review / approval
def book_hotel(hotel_name: str):
"""Book a hotel"""
# highlight-next-line
response = interrupt( # (1)!
f"Trying to call `book_hotel` with args {{'hotel_name': {hotel_name}}}. "
"Please approve or suggest edits."
)
if response["type"] == "accept":
pass
elif response["type"] == "edit":
hotel_name = response["args"]["hotel_name"]
else:
raise ValueError(f"Unknown response type: {response['type']}")
return f"Successfully booked a stay at {hotel_name}."
# highlight-next-line
checkpointer = InMemorySaver() # (2)!
agent = create_react_agent(
model="anthropic:claude-3-5-sonnet-latest",
tools=[book_hotel],
# highlight-next-line
checkpointer=checkpointer, # (3)!
)
```
1. The [`interrupt` function][langgraph.types.interrupt] pauses the agent graph at a specific node. In this case, we call `interrupt()` at the beginning of the tool function, which pauses the graph at the node that executes the tool. The information inside `interrupt()` (e.g., tool calls) can be presented to a human, and the graph can be resumed with the user input (tool call approval, edit or feedback).
2. The `InMemorySaver` is used to store the agent state at every step in the tool calling loop. This enables [short-term memory](./memory.md#short-term-memory) and [human-in-the-loop](./human-in-the-loop.md) capabilities. In this example, we use `InMemorySaver` to store the agent state in memory. In a production application, the agent state will be stored in a database.
3. Initialize the agent with the `checkpointer`.
Run the agent with the `stream()` method, passing the `config` object to specify the thread ID. This allows the agent to resume the same conversation on future invocations.
```python
config = {
"configurable": {
# highlight-next-line
"thread_id": "1"
}
}
for chunk in agent.stream(
{"messages": [{"role": "user", "content": "book a stay at McKittrick hotel"}]},
# highlight-next-line
config
):
print(chunk)
print("\n")
```
> You should see that the agent runs until it reaches the `interrupt()` call, at which point it pauses and waits for human input.
Resume the agent with a `Command(resume=...)` to continue based on human input.
```python
from langgraph.types import Command
for chunk in agent.stream(
# highlight-next-line
Command(resume={"type": "accept"}), # (1)!
# Command(resume={"type": "edit", "args": {"hotel_name": "McKittrick Hotel"}}),
config
):
print(chunk)
print("\n")
```
1. The [`interrupt` function][langgraph.types.interrupt] is used in conjunction with the [`Command`][langgraph.types.Command] object to resume the graph with a value provided by the human.
## Using with Agent Inbox
You can create a wrapper to add interrupts to *any* tool.
The example below provides a reference implementation compatible with [Agent Inbox UI](https://github.com/langchain-ai/agent-inbox) and [Agent Chat UI](https://github.com/langchain-ai/agent-chat-ui).
```python title="Wrapper that adds human-in-the-loop to any tool"
from typing import Callable
from langchain_core.tools import BaseTool, tool as create_tool
from langchain_core.runnables import RunnableConfig
from langgraph.types import interrupt
from langgraph.prebuilt.interrupt import HumanInterruptConfig, HumanInterrupt
def add_human_in_the_loop(
tool: Callable | BaseTool,
*,
interrupt_config: HumanInterruptConfig = None,
) -> BaseTool:
"""Wrap a tool to support human-in-the-loop review."""
if not isinstance(tool, BaseTool):
tool = create_tool(tool)
if interrupt_config is None:
interrupt_config = {
"allow_accept": True,
"allow_edit": True,
"allow_respond": True,
}
@create_tool( # (1)!
tool.name,
description=tool.description,
args_schema=tool.args_schema
)
def call_tool_with_interrupt(config: RunnableConfig, **tool_input):
request: HumanInterrupt = {
"action_request": {
"action": tool.name,
"args": tool_input
},
"config": interrupt_config,
"description": "Please review the tool call"
}
# highlight-next-line
response = interrupt([request])[0] # (2)!
# approve the tool call
if response["type"] == "accept":
tool_response = tool.invoke(tool_input, config)
# update tool call args
elif response["type"] == "edit":
tool_input = response["args"]["args"]
tool_response = tool.invoke(tool_input, config)
# respond to the LLM with user feedback
elif response["type"] == "response":
user_feedback = response["args"]
tool_response = user_feedback
else:
raise ValueError(f"Unsupported interrupt response type: {response['type']}")
return tool_response
return call_tool_with_interrupt
```
1. This wrapper creates a new tool that calls `interrupt()` **before** executing the wrapped tool.
2. `interrupt()` is using special input and output format that's expected by [Agent Inbox UI](https://github.com/langchain-ai/agent-inbox):
- a list of [`HumanInterrupt`][langgraph.prebuilt.interrupt.HumanInterrupt] objects is sent to `AgentInbox` render interrupt information to the end user
- resume value is provided by `AgentInbox` as a list (i.e., `Command(resume=[...])`)
You can use the `add_human_in_the_loop` wrapper to add `interrupt()` to any tool without having to add it *inside* the tool:
```python
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.prebuilt import create_react_agent
# highlight-next-line
checkpointer = InMemorySaver()
def book_hotel(hotel_name: str):
"""Book a hotel"""
return f"Successfully booked a stay at {hotel_name}."
agent = create_react_agent(
model="anthropic:claude-3-5-sonnet-latest",
tools=[
# highlight-next-line
add_human_in_the_loop(book_hotel), # (1)!
],
# highlight-next-line
checkpointer=checkpointer,
)
config = {"configurable": {"thread_id": "1"}}
# Run the agent
for chunk in agent.stream(
{"messages": [{"role": "user", "content": "book a stay at McKittrick hotel"}]},
# highlight-next-line
config
):
print(chunk)
print("\n")
```
1. The `add_human_in_the_loop` wrapper is used to add `interrupt()` to the tool. This allows the agent to pause execution and wait for human input before proceeding with the tool call.
> You should see that the agent runs until it reaches the `interrupt()` call,
> at which point it pauses and waits for human input.
Resume the agent with a `Command(resume=...)` to continue based on human input.
```python
from langgraph.types import Command
for chunk in agent.stream(
# highlight-next-line
Command(resume=[{"type": "accept"}]),
# Command(resume=[{"type": "edit", "args": {"args": {"hotel_name": "McKittrick Hotel"}}}]),
config
):
print(chunk)
print("\n")
```
## Additional resources
* [Human-in-the-loop in LangGraph](../concepts/human_in_the_loop.md)
+43 -112
View File
@@ -7,125 +7,57 @@ hide:
- tags
---
# Use MCP
# MCP Integration
The Model Context Protocol (MCP) is an open protocol that standardizes how applications provide tools and context to language models. LangGraph agents can use tools defined on MCP servers through the `langchain-mcp-adapters` library.
[Model Context Protocol (MCP)](https://modelcontextprotocol.io/introduction) is an open protocol that standardizes how applications provide tools and context to language models. LangGraph agents can use tools defined on MCP servers through the `langchain-mcp-adapters` library.
![MCP](./assets/mcp.png)
Install the `langchain-mcp-adapters` library to use MCP tools in LangGraph:
```bash
pip install langchain-mcp-adapters
```
## Use MCP tools
The `langchain-mcp-adapters` package enables agents to use tools defined across one or more MCP servers.
=== "In an agent"
```python title="Agent using tools defined on MCP servers"
# highlight-next-line
from langchain_mcp_adapters.client import MultiServerMCPClient
from langgraph.prebuilt import create_react_agent
```python title="Agent using tools defined on MCP servers"
# highlight-next-line
from langchain_mcp_adapters.client import MultiServerMCPClient
from langgraph.prebuilt import create_react_agent
# highlight-next-line
client = MultiServerMCPClient(
{
"math": {
"command": "python",
# Replace with absolute path to your math_server.py file
"args": ["/path/to/math_server.py"],
"transport": "stdio",
},
"weather": {
# Ensure you start your weather server on port 8000
"url": "http://localhost:8000/mcp",
"transport": "streamable_http",
}
# highlight-next-line
client = MultiServerMCPClient(
{
"math": {
"command": "python",
# Replace with absolute path to your math_server.py file
"args": ["/path/to/math_server.py"],
"transport": "stdio",
},
"weather": {
# Ensure you start your weather server on port 8000
"url": "http://localhost:8000/mcp",
"transport": "streamable_http",
}
)
}
)
# highlight-next-line
tools = await client.get_tools()
agent = create_react_agent(
"anthropic:claude-3-7-sonnet-latest",
# highlight-next-line
tools = await client.get_tools()
agent = create_react_agent(
"anthropic:claude-3-7-sonnet-latest",
# highlight-next-line
tools
)
math_response = await agent.ainvoke(
{"messages": [{"role": "user", "content": "what's (3 + 5) x 12?"}]}
)
weather_response = await agent.ainvoke(
{"messages": [{"role": "user", "content": "what is the weather in nyc?"}]}
)
```
=== "In a workflow"
```python title="Workflow using MCP tools with ToolNode"
from langchain_mcp_adapters.client import MultiServerMCPClient
from langchain.chat_models import init_chat_model
from langgraph.graph import StateGraph, MessagesState, START, END
from langgraph.prebuilt import ToolNode
# Initialize the model
model = init_chat_model("anthropic:claude-3-5-sonnet-latest")
# Set up MCP client
client = MultiServerMCPClient(
{
"math": {
"command": "python",
# Make sure to update to the full absolute path to your math_server.py file
"args": ["./examples/math_server.py"],
"transport": "stdio",
},
"weather": {
# make sure you start your weather server on port 8000
"url": "http://localhost:8000/mcp/",
"transport": "streamable_http",
}
}
)
tools = await client.get_tools()
# Bind tools to model
model_with_tools = model.bind_tools(tools)
# Create ToolNode
tool_node = ToolNode(tools)
def should_continue(state: MessagesState):
messages = state["messages"]
last_message = messages[-1]
if last_message.tool_calls:
return "tools"
return END
# Define call_model function
async def call_model(state: MessagesState):
messages = state["messages"]
response = await model_with_tools.ainvoke(messages)
return {"messages": [response]}
# Build the graph
builder = StateGraph(MessagesState)
builder.add_node("call_model", call_model)
builder.add_node("tools", tool_node)
builder.add_edge(START, "call_model")
builder.add_conditional_edges(
"call_model",
should_continue,
)
builder.add_edge("tools", "call_model")
# Compile the graph
graph = builder.compile()
# Test the graph
math_response = await graph.ainvoke(
{"messages": [{"role": "user", "content": "what's (3 + 5) x 12?"}]}
)
weather_response = await graph.ainvoke(
{"messages": [{"role": "user", "content": "what is the weather in nyc?"}]}
)
```
tools
)
math_response = await agent.ainvoke(
{"messages": [{"role": "user", "content": "what's (3 + 5) x 12?"}]}
)
weather_response = await agent.ainvoke(
{"messages": [{"role": "user", "content": "what is the weather in nyc?"}]}
)
```
## Custom MCP servers
@@ -174,5 +106,4 @@ if __name__ == "__main__":
## Additional resources
- [MCP documentation](https://modelcontextprotocol.io/introduction)
- [MCP Transport documentation](https://modelcontextprotocol.io/docs/concepts/transports)
- [langchain_mcp_adapters](https://github.com/langchain-ai/langchain-mcp-adapters)
- [MCP Transport documentation](https://modelcontextprotocol.io/docs/concepts/transports)
+423
View File
@@ -0,0 +1,423 @@
---
search:
boost: 2
tags:
- agent
hide:
- tags
---
# Memory
LangGraph supports two types of memory essential for building conversational agents:
- **[Short-term memory](#short-term-memory)**: Tracks the ongoing conversation by maintaining message history within a session.
- **[Long-term memory](#long-term-memory)**: Stores user-specific or application-level data across sessions.
This guide demonstrates how to use both memory types with agents in LangGraph. For a deeper
understanding of memory concepts, refer to the [LangGraph memory documentation](../concepts/memory.md).
<figure markdown="1">
![image](./assets/memory.png){: style="max-height:400px"}
<figcaption>Both <strong>short-term</strong> and <strong>long-term</strong> memory require persistent storage to maintain continuity across LLM interactions. In production environments, this data is typically stored in a database.</figcaption>
</figure>
!!! note "Terminology"
In LangGraph:
- *Short-term memory* is also referred to as **thread-level memory**.
- *Long-term memory* is also called **cross-thread memory**.
A [thread](../concepts/persistence.md#threads) represents a sequence of related runs
grouped by the same `thread_id`.
## Short-term memory
Short-term memory enables agents to track multi-turn conversations. To use it, you must:
1. Provide a `checkpointer` when creating the agent. The `checkpointer` enables [persistence](../concepts/persistence.md) of the agent's state.
2. Supply a `thread_id` in the config when running the agent. The `thread_id` is a unique identifier for the conversation session.
```python
from langgraph.prebuilt import create_react_agent
from langgraph.checkpoint.memory import InMemorySaver
# highlight-next-line
checkpointer = InMemorySaver() # (1)!
def get_weather(city: str) -> str:
"""Get weather for a given city."""
return f"It's always sunny in {city}!"
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_weather],
# highlight-next-line
checkpointer=checkpointer # (2)!
)
# Run the agent
config = {
"configurable": {
# highlight-next-line
"thread_id": "1" # (3)!
}
}
sf_response = agent.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
# highlight-next-line
config
)
# Continue the conversation using the same thread_id
ny_response = agent.invoke(
{"messages": [{"role": "user", "content": "what about new york?"}]},
# highlight-next-line
config # (4)!
)
```
1. The `InMemorySaver` is a checkpointer that stores the agent's state in memory. In a production setting, you would typically use a database or other persistent storage. Please review the [checkpointer documentation](../reference/checkpoints.md) for more options. If you're deploying with **LangGraph Platform**, the platform will provide a production-ready checkpointer for you.
2. The `checkpointer` is passed to the agent. This enables the agent to persist its state across invocations.
3. A unique `thread_id` is provided in the config. This ID is used to identify the conversation session. The value is controlled by the user and can be any string.
4. The agent will continue the conversation using the same `thread_id`. This will allow the agent to infer that the user is asking specifically about the **weather** in New York.
When the agent is invoked the second time with the same `thread_id`, the original message history from the first conversation is automatically included, allowing the agent to infer that the user is asking specifically about the **weather** in New York.
!!! Note "LangGraph Platform provides a production-ready checkpointer"
If you're using [LangGraph Platform](./deployment.md), during deployment your checkpointer will be automatically configured to use a production-ready database.
### Manage message history
Long conversations can exceed the LLM's context window. Common solutions are:
* [Summarization](#summarize-message-history): Maintain a running summary of the conversation
* [Trimming](#trim-message-history): Remove first or last N messages in the history
This allows the agent to keep track of the conversation without exceeding the LLM's context window.
To manage message history, specify `pre_model_hook` — a function ([node](../concepts/low_level.md#nodes)) that will always run before calling the language model.
#### Summarize message history
<figure markdown="1">
![image](./assets/summary.png){: style="max-height:400px"}
<figcaption>Long conversations can exceed the LLM's context window. A common solution is to maintain a running summary of the conversation. This allows the agent to keep track of the conversation without exceeding the LLM's context window.
</figcaption>
</figure>
To summarize message history, you can use [`pre_model_hook`][langgraph.prebuilt.chat_agent_executor.create_react_agent] with a prebuilt [`SummarizationNode`](https://langchain-ai.github.io/langmem/reference/short_term/#langmem.short_term.SummarizationNode):
```python
from langchain_anthropic import ChatAnthropic
from langmem.short_term import SummarizationNode
from langchain_core.messages.utils import count_tokens_approximately
from langgraph.prebuilt import create_react_agent
from langgraph.prebuilt.chat_agent_executor import AgentState
from langgraph.checkpoint.memory import InMemorySaver
from typing import Any
model = ChatAnthropic(model="claude-3-7-sonnet-latest")
summarization_node = SummarizationNode( # (1)!
token_counter=count_tokens_approximately,
model=model,
max_tokens=384,
max_summary_tokens=128,
output_messages_key="llm_input_messages",
)
class State(AgentState):
# NOTE: we're adding this key to keep track of previous summary information
# to make sure we're not summarizing on every LLM call
# highlight-next-line
context: dict[str, Any] # (2)!
checkpointer = InMemorySaver() # (3)!
agent = create_react_agent(
model=model,
tools=tools,
# highlight-next-line
pre_model_hook=summarization_node, # (4)!
# highlight-next-line
state_schema=State, # (5)!
checkpointer=checkpointer,
)
```
1. The `InMemorySaver` is a checkpointer that stores the agent's state in memory. In a production setting, you would typically use a database or other persistent storage. Please review the [checkpointer documentation](../reference/checkpoints.md) for more options. If you're deploying with **LangGraph Platform**, the platform will provide a production-ready checkpointer for you.
2. The `context` key is added to the agent's state. The key contains book-keeping information for the summarization node. It is used to keep track of the last summary information and ensure that the agent doesn't summarize on every LLM call, which can be inefficient.
3. The `checkpointer` is passed to the agent. This enables the agent to persist its state across invocations.
4. The `pre_model_hook` is set to the `SummarizationNode`. This node will summarize the message history before sending it to the LLM. The summarization node will automatically handle the summarization process and update the agent's state with the new summary. You can replace this with a custom implementation if you prefer. Please see the [create_react_agent][langgraph.prebuilt.chat_agent_executor.create_react_agent] API reference for more details.
5. The `state_schema` is set to the `State` class, which is the custom state that contains an extra `context` key.
#### Trim message history
To trim message history, you can use [`pre_model_hook`][langgraph.prebuilt.chat_agent_executor.create_react_agent] with [`trim_messages`](https://python.langchain.com/api_reference/core/messages/langchain_core.messages.utils.trim_messages.html) function:
```python
# highlight-next-line
from langchain_core.messages.utils import (
# highlight-next-line
trim_messages,
# highlight-next-line
count_tokens_approximately
# highlight-next-line
)
from langgraph.prebuilt import create_react_agent
# This function will be called every time before the node that calls LLM
def pre_model_hook(state):
trimmed_messages = trim_messages(
state["messages"],
strategy="last",
token_counter=count_tokens_approximately,
max_tokens=384,
start_on="human",
end_on=("human", "tool"),
)
# highlight-next-line
return {"llm_input_messages": trimmed_messages}
checkpointer = InMemorySaver()
agent = create_react_agent(
model,
tools,
# highlight-next-line
pre_model_hook=pre_model_hook,
checkpointer=checkpointer,
)
```
To learn more about using `pre_model_hook` for managing message history, see this [how-to guide](../how-tos/create-react-agent-manage-message-history.ipynb)
### Read in tools { #read-short-term }
LangGraph allows agent to access its short-term memory (state) inside the tools.
```python
from typing import Annotated
from langgraph.prebuilt import InjectedState, create_react_agent
class CustomState(AgentState):
# highlight-next-line
user_id: str
def get_user_info(
# highlight-next-line
state: Annotated[CustomState, InjectedState]
) -> str:
"""Look up user info."""
# highlight-next-line
user_id = state["user_id"]
return "User is John Smith" if user_id == "user_123" else "Unknown user"
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_user_info],
# highlight-next-line
state_schema=CustomState,
)
agent.invoke({
"messages": "look up user information",
# highlight-next-line
"user_id": "user_123"
})
```
See the [Context](./context.md#__tabbed_2_2) guide for more information.
### Write from tools { #write-short-term }
To modify the agent's short-term memory (state) during execution, you can return state updates directly from the tools. This is useful for persisting intermediate results or making information accessible to subsequent tools or prompts.
```python
from typing import Annotated
from langchain_core.tools import InjectedToolCallId
from langchain_core.runnables import RunnableConfig
from langchain_core.messages import ToolMessage
from langgraph.prebuilt import InjectedState, create_react_agent
from langgraph.prebuilt.chat_agent_executor import AgentState
from langgraph.types import Command
class CustomState(AgentState):
# highlight-next-line
user_name: str
def update_user_info(
tool_call_id: Annotated[str, InjectedToolCallId],
config: RunnableConfig
) -> Command:
"""Look up and update user info."""
user_id = config["configurable"].get("user_id")
name = "John Smith" if user_id == "user_123" else "Unknown user"
# highlight-next-line
return Command(update={
# highlight-next-line
"user_name": name,
# update the message history
"messages": [
ToolMessage(
"Successfully looked up user information",
tool_call_id=tool_call_id
)
]
})
def greet(
# highlight-next-line
state: Annotated[CustomState, InjectedState]
) -> str:
"""Use this to greet the user once you found their info."""
user_name = state["user_name"]
return f"Hello {user_name}!"
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[update_user_info, greet],
# highlight-next-line
state_schema=CustomState
)
agent.invoke(
{"messages": [{"role": "user", "content": "greet the user"}]},
# highlight-next-line
config={"configurable": {"user_id": "user_123"}}
)
```
For more details, see [how to update state from tools](../how-tos/tool-calling.ipynb#update).
## Long-term memory
Use long-term memory to store user-specific or application-specific data across conversations. This is useful for applications like chatbots, where you want to remember user preferences or other information.
To use long-term memory, you need to:
1. [Configure a store](../how-tos/persistence.ipynb#add-long-term-memory) to persist data across invocations.
2. Use the [`get_store`][langgraph.config.get_store] function to access the store from within tools or prompts.
### Read { #read-long-term }
```python title="A tool the agent can use to look up user information"
from langchain_core.runnables import RunnableConfig
from langgraph.config import get_store
from langgraph.prebuilt import create_react_agent
from langgraph.store.memory import InMemoryStore
# highlight-next-line
store = InMemoryStore() # (1)!
# highlight-next-line
store.put( # (2)!
("users",), # (3)!
"user_123", # (4)!
{
"name": "John Smith",
"language": "English",
} # (5)!
)
def get_user_info(config: RunnableConfig) -> str:
"""Look up user info."""
# Same as that provided to `create_react_agent`
# highlight-next-line
store = get_store() # (6)!
user_id = config["configurable"].get("user_id")
# highlight-next-line
user_info = store.get(("users",), user_id) # (7)!
return str(user_info.value) if user_info else "Unknown user"
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[get_user_info],
# highlight-next-line
store=store # (8)!
)
# Run the agent
agent.invoke(
{"messages": [{"role": "user", "content": "look up user information"}]},
# highlight-next-line
config={"configurable": {"user_id": "user_123"}}
)
```
1. The `InMemoryStore` is a store that stores data in memory. In a production setting, you would typically use a database or other persistent storage. Please review the [store documentation](../reference/store.md) for more options. If you're deploying with **LangGraph Platform**, the platform will provide a production-ready store for you.
2. For this example, we write some sample data to the store using the `put` method. Please see the [BaseStore.put][langgraph.store.base.BaseStore.put] API reference for more details.
3. The first argument is the namespace. This is used to group related data together. In this case, we are using the `users` namespace to group user data.
4. A key within the namespace. This example uses a user ID for the key.
5. The data that we want to store for the given user.
6. The `get_store` function is used to access the store. You can call it from anywhere in your code, including tools and prompts. This function returns the store that was passed to the agent when it was created.
7. The `get` method is used to retrieve data from the store. The first argument is the namespace, and the second argument is the key. This will return a `StoreValue` object, which contains the value and metadata about the value.
8. The `store` is passed to the agent. This enables the agent to access the store when running tools. You can also use the `get_store` function to access the store from anywhere in your code.
### Write { #write-long-term }
```python title="Example of a tool that updates user information"
from typing_extensions import TypedDict
from langgraph.config import get_store
from langgraph.prebuilt import create_react_agent
from langgraph.store.memory import InMemoryStore
store = InMemoryStore() # (1)!
class UserInfo(TypedDict): # (2)!
name: str
def save_user_info(user_info: UserInfo, config: RunnableConfig) -> str: # (3)!
"""Save user info."""
# Same as that provided to `create_react_agent`
# highlight-next-line
store = get_store() # (4)!
user_id = config["configurable"].get("user_id")
# highlight-next-line
store.put(("users",), user_id, user_info) # (5)!
return "Successfully saved user info."
agent = create_react_agent(
model="anthropic:claude-3-7-sonnet-latest",
tools=[save_user_info],
# highlight-next-line
store=store
)
# Run the agent
agent.invoke(
{"messages": [{"role": "user", "content": "My name is John Smith"}]},
# highlight-next-line
config={"configurable": {"user_id": "user_123"}} # (6)!
)
# You can access the store directly to get the value
store.get(("users",), "user_123").value
```
1. The `InMemoryStore` is a store that stores data in memory. In a production setting, you would typically use a database or other persistent storage. Please review the [store documentation](../reference/store.md) for more options. If you're deploying with **LangGraph Platform**, the platform will provide a production-ready store for you.
2. The `UserInfo` class is a `TypedDict` that defines the structure of the user information. The LLM will use this to format the response according to the schema.
3. The `save_user_info` function is a tool that allows an agent to update user information. This could be useful for a chat application where the user wants to update their profile information.
4. The `get_store` function is used to access the store. You can call it from anywhere in your code, including tools and prompts. This function returns the store that was passed to the agent when it was created.
5. The `put` method is used to store data in the store. The first argument is the namespace, and the second argument is the key. This will store the user information in the store.
6. The `user_id` is passed in the config. This is used to identify the user whose information is being updated.
### Semantic search
LangGraph also allows you to [search](https://langchain-ai.github.io/langgraph/how-tos/memory/semantic-search/#using-in-create-react-agent) for items in long-term memory by semantic similarity.
### Prebuilt memory tools
**LangMem** is a LangChain-maintained library that offers tools for managing long-term memories in your agent. See the [LangMem documentation](https://langchain-ai.github.io/langmem/) for usage examples.
## Additional resources
* [Memory in LangGraph](../concepts/memory.md)
+213 -94
View File
@@ -1,78 +1,233 @@
---
search:
boost: 2
tags:
- anthropic
- openai
- agent
hide:
- tags
---
# Models
LangGraph provides built-in support for [LLMs (language models)](https://python.langchain.com/docs/concepts/chat_models/) via the LangChain library. This makes it easy to integrate various LLMs into your agents and workflows.
This page describes how to configure the chat model used by an agent.
## Tool calling support
To enable tool-calling agents, the underlying LLM must support [tool calling](https://python.langchain.com/docs/concepts/tool_calling/).
Compatible models can be found in the [LangChain integrations directory](https://python.langchain.com/docs/integrations/chat/).
## Specifying a model by name
You can configure an agent with a model name string:
=== "OpenAI"
```python
import os
from langgraph.prebuilt import create_react_agent
os.environ["OPENAI_API_KEY"] = "sk-..."
agent = create_react_agent(
# highlight-next-line
model="openai:gpt-4.1",
# other parameters
)
```
=== "Anthropic"
```python
import os
from langgraph.prebuilt import create_react_agent
os.environ["ANTHROPIC_API_KEY"] = "sk-..."
agent = create_react_agent(
# highlight-next-line
model="anthropic:claude-3-7-sonnet-latest",
# other parameters
)
```
=== "Azure"
```python
import os
from langgraph.prebuilt import create_react_agent
os.environ["AZURE_OPENAI_API_KEY"] = "..."
os.environ["AZURE_OPENAI_ENDPOINT"] = "..."
os.environ["OPENAI_API_VERSION"] = "2025-03-01-preview"
agent = create_react_agent(
# highlight-next-line
model="azure_openai:gpt-4.1",
# other parameters
)
```
=== "Google Gemini"
```python
import os
from langgraph.prebuilt import create_react_agent
os.environ["GOOGLE_API_KEY"] = "..."
agent = create_react_agent(
# highlight-next-line
model="google_genai:gemini-2.0-flash",
# other parameters
)
```
=== "AWS Bedrock"
```python
from langgraph.prebuilt import create_react_agent
# Follow the steps here to configure your credentials:
# https://docs.aws.amazon.com/bedrock/latest/userguide/getting-started.html
agent = create_react_agent(
# highlight-next-line
model="bedrock_converse:anthropic.claude-3-5-sonnet-20240620-v1:0",
# other parameters
)
```
## Initialize a model
## Using `init_chat_model`
Use [`init_chat_model`](https://python.langchain.com/docs/how_to/chat_models_universal_init/) to initialize models:
The [`init_chat_model`](https://python.langchain.com/docs/how_to/chat_models_universal_init/) utility simplifies model initialization with configurable parameters:
{% include-markdown "../../snippets/chat_model_tabs.md" %}
=== "OpenAI"
### Instantiate a model directly
```
pip install -U "langchain[openai]"
```
```python
import os
from langchain.chat_models import init_chat_model
os.environ["OPENAI_API_KEY"] = "sk-..."
model = init_chat_model(
"openai:gpt-4.1",
temperature=0,
# other parameters
)
```
=== "Anthropic"
```
pip install -U "langchain[anthropic]"
```
```python
import os
from langchain.chat_models import init_chat_model
os.environ["ANTHROPIC_API_KEY"] = "sk-..."
model = init_chat_model(
"anthropic:claude-3-5-sonnet-latest",
temperature=0,
# other parameters
)
```
=== "Azure"
```
pip install -U "langchain[openai]"
```
```python
import os
from langchain.chat_models import init_chat_model
os.environ["AZURE_OPENAI_API_KEY"] = "..."
os.environ["AZURE_OPENAI_ENDPOINT"] = "..."
os.environ["OPENAI_API_VERSION"] = "2025-03-01-preview"
model = init_chat_model(
"azure_openai:gpt-4.1",
azure_deployment=os.environ["AZURE_OPENAI_DEPLOYMENT_NAME"],
temperature=0,
# other parameters
)
```
=== "Google Gemini"
```
pip install -U "langchain[google-genai]"
```
```python
import os
from langchain.chat_models import init_chat_model
os.environ["GOOGLE_API_KEY"] = "..."
model = init_chat_model(
"google_genai:gemini-2.0-flash",
temperature=0,
# other parameters
)
```
=== "AWS Bedrock"
```
pip install -U "langchain[aws]"
```
```python
from langchain.chat_models import init_chat_model
# Follow the steps here to configure your credentials:
# https://docs.aws.amazon.com/bedrock/latest/userguide/getting-started.html
model = init_chat_model(
"anthropic.claude-3-5-sonnet-20240620-v1:0",
model_provider="bedrock_converse",
temperature=0,
# other parameters
)
```
Refer to the [API reference](https://python.langchain.com/api_reference/langchain/chat_models/langchain.chat_models.base.init_chat_model.html) for advanced options.
## Using provider-specific LLMs
If a model provider is not available via `init_chat_model`, you can instantiate the provider's model class directly. The model must implement the [BaseChatModel interface](https://python.langchain.com/api_reference/core/language_models/langchain_core.language_models.chat_models.BaseChatModel.html) and support tool calling:
```python
# Anthropic is already supported by `init_chat_model`,
# but you can also instantiate it directly.
from langchain_anthropic import ChatAnthropic
from langgraph.prebuilt import create_react_agent
model = ChatAnthropic(
model="claude-3-7-sonnet-latest",
temperature=0,
max_tokens=2048
model="claude-3-7-sonnet-latest",
temperature=0,
max_tokens=2048
)
agent = create_react_agent(
# highlight-next-line
model=model,
# other parameters
)
```
!!! important "Tool calling support"
!!! note "Illustrative example"
If you are building an agent or workflow that requires the model to call external tools, ensure that the underlying
language model supports [tool calling](../concepts/tools.md). Compatible models can be found in the [LangChain integrations directory](https://python.langchain.com/docs/integrations/chat/).
The example above uses `ChatAnthropic`, which is already supported by `init_chat_model`. This pattern is shown to illustrate how to manually instantiate a model not available through init_chat_model.
## Use in an agent
When using `create_react_agent` you can specify the model by its name string, which is a shorthand for initializing the model using `init_chat_model`. This allows you to use the model without needing to import or instantiate it directly.
=== "model name"
```python
from langgraph.prebuilt import create_react_agent
create_react_agent(
# highlight-next-line
model="anthropic:claude-3-7-sonnet-latest",
# other parameters
)
```
=== "model instance"
```python
from langchain_anthropic import ChatAnthropic
from langgraph.prebuilt import create_react_agent
model = ChatAnthropic(
model="claude-3-7-sonnet-latest",
temperature=0,
max_tokens=2048
)
# Alternatively
# model = init_chat_model("anthropic:claude-3-7-sonnet-latest")
agent = create_react_agent(
# highlight-next-line
model=model,
# other parameters
)
```
## Advanced model configuration
### Disable streaming
## Disable streaming
To disable streaming of the individual LLM tokens, set `disable_streaming=True` when initializing the model:
@@ -102,7 +257,7 @@ To disable streaming of the individual LLM tokens, set `disable_streaming=True`
Refer to the [API reference](https://python.langchain.com/api_reference/core/language_models/langchain_core.language_models.chat_models.BaseChatModel.html#langchain_core.language_models.chat_models.BaseChatModel.disable_streaming) for more information on `disable_streaming`
### Add model fallbacks
## Adding model fallbacks
You can add a fallback to a different model or a different LLM provider using `model.with_fallbacks([...])`:
@@ -137,43 +292,7 @@ You can add a fallback to a different model or a different LLM provider using `m
See this [guide](https://python.langchain.com/docs/how_to/fallbacks/#fallback-to-better-model) for more information on model fallbacks.
### Use the built-in rate limiter
Langchain includes a built-in in-memory rate limiter. This rate limiter is thread safe and can be shared by multiple threads in the same process.
```python
from langchain_core.rate_limiters import InMemoryRateLimiter
from langchain_anthropic import ChatAnthropic
rate_limiter = InMemoryRateLimiter(
requests_per_second=0.1, # <-- Super slow! We can only make a request once every 10 seconds!!
check_every_n_seconds=0.1, # Wake up every 100 ms to check whether allowed to make a request,
max_bucket_size=10, # Controls the maximum burst size.
)
model = ChatAnthropic(
model_name="claude-3-opus-20240229",
rate_limiter=rate_limiter
)
```
See the LangChain docs for more information on how to [handle rate limiting](https://python.langchain.com/docs/how_to/chat_model_rate_limiting/).
## Bring your own model
If your desired LLM isn't officially supported by LangChain, consider these options:
1. **Implement a custom LangChain chat model**: Create a model conforming to the [LangChain chat model interface](https://python.langchain.com/docs/how_to/custom_chat_model/). This enables full compatibility with LangGraph's agents and workflows but requires understanding of the LangChain framework.
2. **Direct invocation with custom streaming**: Use your model directly by [adding custom streaming logic](../how-tos/streaming.md#use-with-any-llm) with `StreamWriter`.
Refer to the [custom streaming documentation](../how-tos/streaming.md#use-with-any-llm) for guidance. This approach suits custom workflows where prebuilt agent integration is not necessary.
## Additional resources
- [Multimodal inputs](https://python.langchain.com/docs/how_to/multimodal_inputs/)
- [Structured outputs](https://python.langchain.com/docs/how_to/structured_output/)
- [Model integration directory](https://python.langchain.com/docs/integrations/chat/)
- [Force model to call a specific tool](https://python.langchain.com/docs/how_to/tool_choice/)
- [All chat model how-to guides](https://python.langchain.com/docs/how_to/#chat-models)
- [Chat model integrations](https://python.langchain.com/docs/integrations/chat/)
- [Universal initialization with `init_chat_model`](https://python.langchain.com/docs/how_to/chat_models_universal_init/)
+7 -7
View File
@@ -8,9 +8,9 @@ hide:
- tags
---
# Agent development using prebuilt components
# Agent development with LangGraph
LangGraph provides both low-level primitives and high-level prebuilt components for building agent-based applications. This section focuses on the prebuilt, ready-to-use components designed to help you construct agentic systems quickly and reliably—without the need to implement orchestration, memory, or human feedback handling from scratch.
**LangGraph** provides both low-level primitives and high-level prebuilt components for building agent-based applications. This section focuses on the **prebuilt**, **reusable** components designed to help you construct agentic systems quickly and reliably—without the need to implement orchestration, memory, or human feedback handling from scratch.
## What is an agent?
@@ -27,10 +27,10 @@ The LLM operates in a loop. In each iteration, it selects a tool to invoke, prov
LangGraph includes several capabilities essential for building robust, production-ready agentic systems:
- [**Memory integration**](../how-tos/memory/add-memory.md): Native support for *short-term* (session-based) and *long-term* (persistent across sessions) memory, enabling stateful behaviors in chatbots and assistants.
- [**Human-in-the-loop control**](../concepts/human_in_the_loop.md): Execution can pause *indefinitely* to await human feedback—unlike websocket-based solutions limited to real-time interaction. This enables asynchronous approval, correction, or intervention at any point in the workflow.
- [**Memory integration**](./memory.md): Native support for *short-term* (session-based) and *long-term* (persistent across sessions) memory, enabling stateful behaviors in chatbots and assistants.
- [**Human-in-the-loop control**](./human-in-the-loop.md): Execution can pause *indefinitely* to await human feedback—unlike websocket-based solutions limited to real-time interaction. This enables asynchronous approval, correction, or intervention at any point in the workflow.
- [**Streaming support**](../how-tos/streaming.md): Real-time streaming of agent state, model tokens, tool outputs, or combined streams.
- [**Deployment tooling**](../tutorials/langgraph-platform/local-server.md): Includes infrastructure-free deployment tools. [**LangGraph Platform**](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform/) supports testing, debugging, and deployment.
- [**Deployment tooling**](./deployment.md): Includes infrastructure-free deployment tools. [**LangGraph Platform**](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform/) supports testing, debugging, and deployment.
- **[Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio/)**: A visual IDE for inspecting and debugging workflows.
- Supports multiple [**deployment options**](https://langchain-ai.github.io/langgraph/concepts/deployment_options.md) for production.
@@ -50,7 +50,7 @@ The high-level components are organized into several packages, each with a speci
| `langgraph-supervisor` | Tools for building [**supervisor**](./multi-agent.md#supervisor) agents | `pip install -U langgraph-supervisor` |
| `langgraph-swarm` | Tools for building a [**swarm**](./multi-agent.md#swarm) multi-agent system | `pip install -U langgraph-swarm` |
| `langchain-mcp-adapters` | Interfaces to [**MCP servers**](./mcp.md) for tool and resource integration | `pip install -U langchain-mcp-adapters` |
| `langmem` | Agent memory management: [**short-term and long-term**](../how-tos/memory/add-memory.md) | `pip install -U langmem` |
| `langmem` | Agent memory management: [**short-term and long-term**](./memory.md) | `pip install -U langmem` |
| `agentevals` | Utilities to [**evaluate agent performance**](./evals.md) | `pip install -U agentevals` |
## Visualize an agent graph
@@ -60,7 +60,7 @@ Use the following tool to visualize the graph generated by
and to view an outline of the corresponding code.
It allows you to explore the infrastructure of the agent as defined by the presence of:
* [`tools`](../how-tos/tool-calling.md): A list of tools (functions, APIs, or other callable objects) that the agent can use to perform tasks.
* [`tools`](../agents/tools.md): A list of tools (functions, APIs, or other callable objects) that the agent can use to perform tasks.
* [`pre_model_hook`](../how-tos/create-react-agent-manage-message-history.ipynb): A function that is called before the model is invoked. It can be used to condense messages or perform other preprocessing tasks.
* `post_model_hook`: A function that is called after the model is invoked. It can be used to implement guardrails, human-in-the-loop flows, or other postprocessing tasks.
* [`response_format`](../agents/agents.md#6-configure-structured-output): A data structure used to constrain the type of the final output, e.g., a `pydantic` `BaseModel`.
+3 -3
View File
@@ -1,10 +1,10 @@
[//]: # (This file is automatically generated using a script in docs/_scripts. Do not edit this file directly!)
# Community Agents
# Community agents
If youre looking for other prebuilt libraries, explore the community-built options
below. These libraries can extend LangGraph's functionality in various ways.
## 📚 Available Libraries
## 📚 Available libraries
[//]: # (This file is automatically generated using a script in docs/_scripts. Do not edit this file directly!)
| Name | GitHub URL | Description | Weekly Downloads | Stars |
@@ -23,7 +23,7 @@ below. These libraries can extend LangGraph's functionality in various ways.
| **langgraph-reflection** | [langchain-ai/langgraph-reflection](https://github.com/langchain-ai/langgraph-reflection) | LangGraph agent that runs a reflection step. | -12345 | ![GitHub stars](https://img.shields.io/github/stars/langchain-ai/langgraph-reflection?style=social)
| **langgraph-codeact** | [langchain-ai/langgraph-codeact](https://github.com/langchain-ai/langgraph-codeact) | LangGraph implementation of CodeAct agent that generates and executes code instead of tool calling. | -12345 | ![GitHub stars](https://img.shields.io/github/stars/langchain-ai/langgraph-codeact?style=social)
## ✨ Contributing Your Library
## ✨ Contributing your library
Have you built an awesome open-source library using LangGraph? We'd love to feature
your project on the official LangGraph documentation pages! 🏆
+1 -1
View File
@@ -10,7 +10,7 @@ hide:
# Running agents
Agents support both synchronous and asynchronous execution using either `.invoke()` / `await .ainvoke()` for full responses, or `.stream()` / `.astream()` for **incremental** [streaming](../how-tos/streaming.md) output. This section explains how to provide input, interpret output, enable streaming, and control execution limits.
Agents support both synchronous and asynchronous execution using either `.invoke()` / `await .ainvoke()` for full responses, or `.stream()` / `.astream()` for **incremental** [streaming](streaming.md) output. This section explains how to provide input, interpret output, enable streaming, and control execution limits.
## Basic usage
+1
View File
@@ -0,0 +1 @@
delete me
+2 -2
View File
@@ -13,7 +13,7 @@ You can use a prebuilt chat UI for interacting with any LangGraph agent through
## Run agent in UI
First, set up LangGraph API server [locally](../tutorials/langgraph-platform/local-server.md) or deploy your agent on [LangGraph Platform](https://langchain-ai.github.io/langgraph/cloud/quick_start/).
First, set up LangGraph API server [locally](./deployment.md#launch-langgraph-server-locally) or deploy your agent on [LangGraph Platform](https://langchain-ai.github.io/langgraph/cloud/quick_start/).
Then, navigate to [Agent Chat UI](https://agentchat.vercel.app), or clone the repository and [run the dev server locally](https://github.com/langchain-ai/agent-chat-ui?tab=readme-ov-file#setup):
@@ -25,7 +25,7 @@ Then, navigate to [Agent Chat UI](https://agentchat.vercel.app), or clone the re
## Add human-in-the-loop
Agent Chat UI has full support for [human-in-the-loop](../concepts/human_in_the_loop.md) workflows. To try it out, replace the agent code in `src/agent/graph.py` (from the [deployment](../tutorials/langgraph-platform/local-server.md) guide) with this [agent implementation](../how-tos/human_in_the_loop/add-human-in-the-loop.md#add-interrupts-to-any-tool):
Agent Chat UI has full support for [human-in-the-loop](../concepts/human_in_the_loop.md) workflows. To try it out, replace the agent code in `src/agent/graph.py` (from the [deployment](./deployment.md) guide) with this [agent implementation](./human-in-the-loop.md#using-with-agent-inbox):
<video controls src="../assets/interrupt-chat-ui.mp4" type="video/mp4"></video>
@@ -1,54 +0,0 @@
# Data Storage and Privacy
This document describes how data is processed in the LangGraph CLI and the LangGraph Server for both the in-memory server (`langgraph dev`) and the local Docker server (`langgraph up`). It also describes what data is tracked when interacting with the hosted LangGraph Studio frontend.
## CLI
LangGraph **CLI** is the command-line interface for building and running LangGraph applications; see the [CLI guide](../../concepts/langgraph_cli.md) to learn more.
By default, calls to most CLI commands log a single analytics event upon invocation. This helps us better prioritize improvements to the CLI experience. Each telemetry event contains the calling process's OS, OS version, Python version, the CLI version, the command name (`dev`, `up`, `run`, etc.), and booleans representing whether a flag was passed to the command. You can see the full analytics logic [here](https://github.com/langchain-ai/langgraph/blob/main/libs/cli/langgraph_cli/analytics.py).
You can disable all CLI telemetry by setting `LANGGRAPH_CLI_NO_ANALYTICS=1`.
## LangGraph Server (in-memory & docker)
The [LangGraph Server](../../concepts/langgraph_server.md) provides a durable execution runtime that relies on persisting checkpoints of your application state, long-term memories, thread metadata, assistants, and similar resources to the local file system or a database. Unless you have deliberately customized the storage location, this information is either written to local disk (for `langgraph dev`) or a PostgreSQL database (for `langgraph up` and in all deployments).
### LangSmith Tracing
When running the LangGraph server (either in-memory or in Docker), LangSmith tracing may be enabled to facilitate faster debugging and offer observability of graph state and LLM prompts in production. You can always disable tracing by setting `LANGSMITH_TRACING=false` in your server's runtime environment.
### In-memory development server (`langgraph dev`)
`langgraph dev` runs an [in-memory development server](../../tutorials/langgraph-platform/local-server.md) as a single Python process, designed for quick development and testing. It saves all checkpointing and memory data to disk within a `.langgraph_api` directory in the current working directory. Apart from the telemetry data described in the [CLI](#cli) section, no data leaves the machine unless you have enabled tracing or your graph code explicitly contacts an external service.
### Standalone Container (`langgraph up`)
`langgraph up` builds your local package into a Docker image and runs the server as a [standalone container](../../concepts/deployment_options.md#standalone-container) consisting of three containers: the API server, a PostgreSQL container, and a Redis container. All persistent data (checkpoints, assistants, etc.) are stored in the PostgreSQL database. Redis is used as a pubsub connection for real-time streaming of events. You can encrypt all checkpoints before saving to the database by setting a valid `LANGGRAPH_AES_KEY` environment variable. You can also specify [TTLs](../../how-tos/ttl/configure_ttl.md) for checkpoints and cross-thread memories in `langgraph.json` to control how long data is stored. All persisted threads, memories, and other data can be deleted via the relevant API endpoints.
Additional API calls are made to confirm that the server has a valid license and to track the number of executed runs and tasks. Periodically, the API server validates the provided license key (or API key).
If you've disabled [tracing](#langsmith-tracing), no user data is persisted externally unless your graph code explicitly contacts an external service.
## Studio
[LangGraph Studio](../../concepts/langgraph_studio.md) is a graphical interface for interacting with your LangGraph server. It does not persist any private data (the data you send to your server is not sent to LangSmith). Though the studio interface is served at [smith.langchain.com](https://smith.langchain.com), it is run in your browser and connects directly to your local LangGraph server so that no data needs to be sent to LangSmith.
If you are logged in, LangSmith does collect some usage analytics to help improve studio's user experience. This includes:
- Page visits and navigation patterns
- User actions (button clicks)
- Browser type and version
- Screen resolution and viewport size
Importantly, no application data or code (or other sensitive configuration details) are collected. All of that is stored in the persistence layer of your LangGraph server. When using Studio anonymously, no account creation is required and usage analytics are not collected.
## Quick reference
In summary, you can opt-out of server-side telemetry by turning off CLI analytics and disabling tracing.
| Variable | Purpose | Default |
| ------------------------------ | ------------------------- | -------------------------------- |
| `LANGGRAPH_CLI_NO_ANALYTICS=1` | Disable CLI analytics | Analytics enabled |
| `LANGSMITH_API_KEY` | Enable LangSmith tracing | Tracing disabled |
| `LANGSMITH_TRACING=false` | Disable LangSmith tracing | Depends on environment |
+12
View File
@@ -0,0 +1,12 @@
# Threads
A thread contains the accumulated state of a sequence of [runs](./runs.md). When a run is executed, the [state](../../concepts/low_level.md#state) of the underlying graph of the assistant will be persisted to the thread.
A thread's current and historical state can be retrieved. To persist state, a thread must be created prior to executing a run.
The state of a thread at a particular point in time is called a [checkpoint](../../concepts/persistence.md#checkpoints). Checkpoints are persisted and can be used to restore the state of a thread at a later time.
## Learn more
* For more on threads and checkpoints, see this section of the [LangGraph conceptual guide](../../concepts/persistence.md).
* The LangGraph Platform API provides several endpoints for creating and managing threads and thread state. See the [API reference](../../cloud/reference/api/api_ref.html#tag/threads) for more details.
-119
View File
@@ -1,119 +0,0 @@
# Egress for Subscription Metrics and Operational Metadata
> **Important: Self Hosted Only**
> This section only applies to customers who are not running in offline mode and assumes you are using a self-hosted LangGraph Platform instance.
> This does not apply to SaaS or Hybrid deployments.
Self-Hosted LangGraph Platform instances store all information locally and will never send sensitive information outside of your network. We currently only track platform usage for billing purposes according to the entitlements in your order. In order to better remotely support our customers, we do require egress to `https://beacon.langchain.com`.
In the future, we will be introducing support diagnostics to help us ensure that the LangGraph Platform is running at an optimal level within your environment.
> **Warning**
> **This will require egress to `https://beacon.langchain.com` from your network.**
> **If using an API key, you will also need to allow egress to `https://api.smith.langchain.com` or `https://eu.api.smith.langchain.com` for API key verification.**
Generally, data that we send to Beacon can be categorized as follows:
- **Subscription Metrics**
- Subscription metrics are used to determine level of access and utilization of LangSmith. This includes, but are not limited to:
- Nodes Executed
- Runs Executed
- License Key Verification
- **Operational Metadata**
- This metadata will contain and collect the above subscription metrics to assist with remote support, allowing the LangChain team to diagnose and troubleshoot performance issues more effectively and proactively.
## Example Payloads
In an effort to maximize transparency, we provide sample payloads here:
### License Verification (If using an Enterprise License)
**Endpoint:**
`POST beacon.langchain.com/v1/beacon/verify`
**Request:**
```json
{
"license": "<YOUR_LICENSE_KEY>"
}
```
**Response:**
```json
{
"token": "Valid JWT" // Short-lived JWT token to avoid repeated license checks
}
```
### Api Key Verification (If using a LangSmith API Key)
**Endpoint:**
`POST api.smith.langchain.com/auth`
**Request:**
```json
"Headers": {
X-Api-Key: <YOUR_API_KEY>
}
```
**Response:**
```json
{
"org_config": {
"org_id": "3a1c2b6f-4430-4b92-8a5b-79b8b567bbc1",
... // Additional organization details
}
}
```
### Usage Reporting
**Endpoint:**
`POST beacon.langchain.com/v1/metadata/submit`
**Request:**
```json
{
"license": "<YOUR_LICENSE_KEY>",
"from_timestamp": "2025-01-06T09:00:00Z",
"to_timestamp": "2025-01-06T10:00:00Z",
"tags": {
"langgraph.python.version": "0.1.0",
"langgraph_api.version": "0.2.0",
"langgraph.platform.revision": "abc123",
"langgraph.platform.variant": "standard",
"langgraph.platform.host": "host-1",
"langgraph.platform.tenant_id": "3a1c2b6f-4430-4b92-8a5b-79b8b567bbc1",
"langgraph.platform.project_id": "c5b5f53a-4716-4326-8967-d4f7f7799735",
"langgraph.platform.plan": "enterprise",
"user_app.uses_indexing": "true",
"user_app.uses_custom_app": "false",
"user_app.uses_custom_auth": "true",
"user_app.uses_thread_ttl": "true",
"user_app.uses_store_ttl": "false"
},
"measures": {
"langgraph.platform.runs": 150,
"langgraph.platform.nodes": 450
},
"logs": []
}
```
**Response:**
```json
"204 No Content"
```
## Our Commitment
LangChain will not store any sensitive information in the Subscription Metrics or Operational Metadata. Any data collected will not be shared with a third party. If you have any concerns about the data being sent, please reach out to your account team.
@@ -3,7 +3,7 @@
Before deploying, review the [conceptual guide for the Self-Hosted Control Plane](../../concepts/langgraph_self_hosted_control_plane.md) deployment option.
!!! info "Important"
The Self-Hosted Control Plane deployment option requires an [Enterprise](../../concepts/plans.md) plan.
The Self-Hosted Control Plane deployment option is currently in beta stage and requires an [Enterprise](../../concepts/plans.md) plan.
## Prerequisites
@@ -23,8 +23,6 @@ Before deploying, review the [conceptual guide for the Self-Hosted Control Plane
kubectl get storageclass
1. Egress to `https://beacon.langchain.com` from your network. This is required for license verification and usage reporting if not running in air-gapped mode. See the [Egress documentation](../../cloud/deployment/egress.md) for more details.
## Setup
1. As part of configuring your Self-Hosted LangSmith instance, you enable the `langgraphPlatform` option. This will provision a few key resources.
@@ -3,7 +3,7 @@
Before deploying, review the [conceptual guide for the Self-Hosted Data Plane](../../concepts/langgraph_self_hosted_data_plane.md) deployment option.
!!! info "Important"
The Self-Hosted Data Plane deployment option requires an [Enterprise](../../concepts/plans.md) plan.
The Self-Hosted Data Plane deployment option is currently in beta stage and requires an [Enterprise](../../concepts/plans.md) plan.
## Prerequisites
@@ -15,15 +15,11 @@ Before deploying, review the [conceptual guide for the Self-Hosted Data Plane](.
### Prerequisites
1. `KEDA` is installed on your cluster.
helm repo add kedacore https://kedacore.github.io/charts
helm repo add kedacore https://kedacore.github.io/charts
helm install keda kedacore/keda --namespace keda --create-namespace
1. A valid `Ingress` controller is installed on your cluster.
1. You have slack space in your cluster for multiple deployments. `Cluster-Autoscaler` is recommended to automatically provision new nodes.
1. You will need to enable egress to two control plane URLs. The listener polls these endpoints for deployments:
https://api.host.langchain.com
https://api.smith.langchain.com
### Setup
@@ -35,6 +31,7 @@ Before deploying, review the [conceptual guide for the Self-Hosted Data Plane](.
1. Configure your `langgraph-dataplane-values.yaml` file.
config:
langgraphPlatformLicenseKey: "" # Your LangGraph Platform license key
langsmithApiKey: "" # API Key of your Workspace
langsmithWorkspaceId: "" # Workspace ID
hostBackendUrl: "https://api.host.langchain.com" # Only override this if on EU
+3 -3
View File
@@ -108,11 +108,11 @@ from langgraph.graph import StateGraph, END, START
from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
from my_agent.utils.state import AgentState # import state
# Define the runtime context
class GraphContext(TypedDict):
# Define the config
class GraphConfig(TypedDict):
model_name: Literal["anthropic", "openai"]
workflow = StateGraph(AgentState, context_schema=GraphContext)
workflow = StateGraph(AgentState, config_schema=GraphConfig)
workflow.add_node("agent", call_model)
workflow.add_node("action", tool_node)
workflow.add_edge(START, "agent")
@@ -121,11 +121,11 @@ from langgraph.graph import StateGraph, END, START
from my_agent.utils.nodes import call_model, should_continue, tool_node # import nodes
from my_agent.utils.state import AgentState # import state
# Define the runtime context
class GraphContext(TypedDict):
# Define the config
class GraphConfig(TypedDict):
model_name: Literal["anthropic", "openai"]
workflow = StateGraph(AgentState, context_schema=GraphContext)
workflow = StateGraph(AgentState, config_schema=GraphConfig)
workflow.add_node("agent", call_model)
workflow.add_node("action", tool_node)
workflow.add_edge(START, "agent")
@@ -24,7 +24,6 @@ Before deploying, review the [conceptual guide for the Standalone Container](../
1. `LANGSMITH_API_KEY`: (if using [Lite](../../concepts/langgraph_server.md#server-versions)) LangSmith API key. This will be used to authenticate ONCE at server start up.
1. `LANGGRAPH_CLOUD_LICENSE_KEY`: (if using [Enterprise](../../concepts/langgraph_data_plane.md#licensing)) LangGraph Platform license key. This will be used to authenticate ONCE at server start up.
1. `LANGSMITH_ENDPOINT`: To send traces to a [self-hosted LangSmith](https://docs.smith.langchain.com/self_hosting) instance, set `LANGSMITH_ENDPOINT` to the hostname of the self-hosted LangSmith instance.
1. Egress to `https://beacon.langchain.com` from your network. This is required for license verification and usage reporting if not running in air-gapped mode. See the [Egress documentation](../../cloud/deployment/egress.md) for more details.
## Kubernetes (Helm)
+42 -186
View File
@@ -1,8 +1,38 @@
# Human-in-the-loop using Server API
# Human-in-the-loop
To review, edit, and approve tool calls in an agent or workflow, use LangGraph's [human-in-the-loop](../../concepts/human_in_the_loop.md) features.
LangGraph supports robust **human-in-the-loop (HIL)** workflows, enabling human intervention at any point in an automated process. This is especially useful in large language model (LLM)-driven applications where model output may require validation, correction, or additional context.
## Dynamic interrupts
Please see [the overview of LangGraph human-in-the-loop](../../concepts/human_in_the_loop.md) features for more information.
## `interrupt`
The [`interrupt` function][langgraph.types.interrupt] in LangGraph enables human-in-the-loop workflows by pausing the graph at a specific node, presenting information to a human, and resuming the graph with their input. It's useful for tasks like approvals, edits, or gathering additional context.
The graph is resumed using a [`Command`][langgraph.types.Command] object that provides the human's response.
**Graph node with `interrupt`:**
```python
# highlight-next-line
from langgraph.types import interrupt, Command
def human_node(state: State):
# highlight-next-line
value = interrupt( # (1)!
{
"text_to_revise": state["some_text"] # (2)!
}
)
return {
"some_text": value # (3)!
}
```
1. `interrupt(...)` pauses execution at `human_node`, surfacing the given payload to a human.
2. Any JSON serializable value can be passed to the `interrupt` function. Here, a dict containing the text to revise.
3. Once resumed, the return value of `interrupt(...)` is the human-provided input, which is used to update the state.
**LangGraph API invoke & resume:**
=== "Python"
@@ -30,7 +60,9 @@ To review, edit, and approve tool calls in an agent or workflow, use LangGraph's
# > [
# > {
# > 'value': {'text_to_revise': 'original text'},
# > 'id': '...',
# > 'resumable': True,
# > 'ns': ['human_node:fc722478-2f21-0578-c572-d9fc4dd07c3b'],
# > 'when': 'during'
# > }
# > ]
@@ -201,7 +233,9 @@ To review, edit, and approve tool calls in an agent or workflow, use LangGraph's
# > [
# > {
# > 'value': {'text_to_revise': 'original text'},
# > 'id': '...',
# > 'resumable': True,
# > 'ns': ['human_node:fc722478-2f21-0578-c572-d9fc4dd07c3b'],
# > 'when': 'during'
# > }
# > ]
@@ -301,186 +335,8 @@ To review, edit, and approve tool calls in an agent or workflow, use LangGraph's
}"
```
## Static interrupts
Static interrupts (also known as static breakpoints) are triggered either before or after a node executes.
!!! warning
Static interrupts are **not** recommended for human-in-the-loop workflows. They are best used for debugging and testing.
You can set static interrupts by specifying `interrupt_before` and `interrupt_after` at compile time:
```python
# highlight-next-line
graph = graph_builder.compile( # (1)!
# highlight-next-line
interrupt_before=["node_a"], # (2)!
# highlight-next-line
interrupt_after=["node_b", "node_c"], # (3)!
)
```
1. The breakpoints are set during `compile` time.
2. `interrupt_before` specifies the nodes where execution should pause before the node is executed.
3. `interrupt_after` specifies the nodes where execution should pause after the node is executed.
Alternatively, you can set static interrupts at run time:
=== "Python"
```python
# highlight-next-line
await client.runs.wait( # (1)!
thread_id,
assistant_id,
inputs=inputs,
# highlight-next-line
interrupt_before=["node_a"], # (2)!
# highlight-next-line
interrupt_after=["node_b", "node_c"] # (3)!
)
```
1. `client.runs.wait` is called with the `interrupt_before` and `interrupt_after` parameters. This is a run-time configuration and can be changed for every invocation.
2. `interrupt_before` specifies the nodes where execution should pause before the node is executed.
3. `interrupt_after` specifies the nodes where execution should pause after the node is executed.
=== "JavaScript"
```js
// highlight-next-line
await client.runs.wait( // (1)!
threadID,
assistantID,
{
input: input,
// highlight-next-line
interruptBefore: ["node_a"], // (2)!
// highlight-next-line
interruptAfter: ["node_b", "node_c"] // (3)!
}
)
```
1. `client.runs.wait` is called with the `interruptBefore` and `interruptAfter` parameters. This is a run-time configuration and can be changed for every invocation.
2. `interruptBefore` specifies the nodes where execution should pause before the node is executed.
3. `interruptAfter` specifies the nodes where execution should pause after the node is executed.
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"interrupt_before\": [\"node_a\"],
\"interrupt_after\": [\"node_b\", \"node_c\"],
\"input\": <INPUT>
}"
```
The following example shows how to add static interrupts:
=== "Python"
```python
from langgraph_sdk import get_client
client = get_client(url=<DEPLOYMENT_URL>)
# Using the graph deployed with the name "agent"
assistant_id = "agent"
# create a thread
thread = await client.threads.create()
thread_id = thread["thread_id"]
# Run the graph until the breakpoint
result = await client.runs.wait(
thread_id,
assistant_id,
input=inputs # (1)!
)
# Resume the graph
await client.runs.wait(
thread_id,
assistant_id,
input=None # (2)!
)
```
1. The graph is run until the first breakpoint is hit.
2. The graph is resumed by passing in `None` for the input. This will run the graph until the next breakpoint is hit.
=== "JavaScript"
```js
import { Client } from "@langchain/langgraph-sdk";
const client = new Client({ apiUrl: <DEPLOYMENT_URL> });
// Using the graph deployed with the name "agent"
const assistantID = "agent";
// create a thread
const thread = await client.threads.create();
const threadID = thread["thread_id"];
// Run the graph until the breakpoint
const result = await client.runs.wait(
threadID,
assistantID,
{ input: input } // (1)!
);
// Resume the graph
await client.runs.wait(
threadID,
assistantID,
{ input: null } // (2)!
);
```
1. The graph is run until the first breakpoint is hit.
2. The graph is resumed by passing in `null` for the input. This will run the graph until the next breakpoint is hit.
=== "cURL"
Create a thread:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads \
--header 'Content-Type: application/json' \
--data '{}'
```
Run the graph until the breakpoint:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"input\": <INPUT>
}"
```
Resume the graph:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\"
}"
```
## Learn more
- [Human-in-the-loop conceptual guide](../../concepts/human_in_the_loop.md): learn more about LangGraph human-in-the-loop features.
- [Common patterns](../../how-tos/human_in_the_loop/add-human-in-the-loop.md#common-patterns): learn how to implement patterns like approving/rejecting actions, requesting user input, tool call review, and validating human input.
- [**LangGraph human-in-the-loop overview**](../../concepts/human_in_the_loop.md): learn more about LangGraph human-in-the-loop features.
- [**Design patterns**](../../how-tos/human_in_the_loop/add-human-in-the-loop.md#design-patterns): learn how to implement patterns like approving/rejecting actions, requesting user input, and more.
- [**How to review tool calls**](./human_in_the_loop_review_tool_calls.md): detailed examples of how to review and approve/edit tool calls or provide feedback to the tool-calling LLM.
+10 -13
View File
@@ -2,20 +2,21 @@
In this guide we will show how to create, configure, and manage an [assistant](../../concepts/assistants.md).
First, as a brief refresher on the concept of runtime context, consider the following simple `call_model` node and context schema. Observe that this node tries to read and use the `model_provider` as defined by the `Runtime` object's `context` property.
First, as a brief refresher on the concept of configurations, consider the following simple `call_model` node and configuration schema. Observe that this node tries to read and use the `model_name` as defined by the `config` object's `configurable`.
=== "Python"
```python
@dataclass
class ContextSchema:
llm_provider: str = "anthropic"
builder = StateGraph(AgentState, context_schema=ContextSchema)
class ConfigSchema(TypedDict):
model_name: str
def call_model(state, runtime: Runtime[ContextSchema]):
builder = StateGraph(AgentState, config_schema=ConfigSchema)
def call_model(state, config):
messages = state["messages"]
model = _get_model(runtime.context.llm_provider)
model_name = config.get('configurable', {}).get("model_name", "anthropic")
model = _get_model(model_name)
response = model.invoke(messages)
# We return a list, because this will get added to the existing list
return {"messages": [response]}
@@ -43,7 +44,7 @@ First, as a brief refresher on the concept of runtime context, consider the foll
}
```
For more information on runtime context, [see here](../../concepts/low_level.md#runtime-context).
For more information on configurations, [see here](../../concepts/low_level.md#configuration).
## Create an assistant
@@ -211,7 +212,6 @@ We have now created an assistant called "Open AI Assistant" that has `model_name
Output:
```
Receiving event of type: metadata
{'run_id': '1ef6746e-5893-67b1-978a-0f1cd4060e16'}
@@ -219,7 +219,6 @@ Output:
Receiving event of type: updates
{'agent': {'messages': [{'content': 'I was created by OpenAI, a research organization focused on developing and advancing artificial intelligence technology.', 'additional_kwargs': {}, 'response_metadata': {'finish_reason': 'stop', 'model_name': 'gpt-4o-2024-05-13', 'system_fingerprint': 'fp_157b3831f5'}, 'type': 'ai', 'name': None, 'id': 'run-e1a6b25c-8416-41f2-9981-f9cfe043f414', 'example': False, 'tool_calls': [], 'invalid_tool_calls': [], 'usage_metadata': None}]}}
```
### LangGraph Platform UI
@@ -232,11 +231,9 @@ Inside your deployment, select the "Assistants" tab. For the assistant you would
To edit the assistant, use the `update` method. This will create a new version of the assistant with the provided edits. See the [Python](https://langchain-ai.github.io/langgraph/cloud/reference/sdk/python_sdk_ref/#langgraph_sdk.client.AssistantsClient.update) and [JS](https://langchain-ai.github.io/langgraph/cloud/reference/sdk/js_ts_sdk_ref/#update) SDK reference docs for more information.
!!! note "Note"
You must pass in the ENTIRE config (and metadata if you are using it). The update endpoint creates new versions completely from scratch and does not rely on previous versions.
You must pass in the ENTIRE config (and metadata if you are using it). The update endpoint creates new versions completely from scratch and does not rely on previous versions.
For example, to update your assistant's system prompt:
=== "Python"
```python
+11 -27
View File
@@ -30,33 +30,17 @@ export default {
Next, define your UI components in your `langgraph.json` configuration:
=== "Python agent"
```json title="langgraph.json"
{
"node_version": "20",
"graphs": {
"agent": "./src/agent.py:graph"
},
"ui": {
"agent": "./src/agent/ui.tsx"
}
}
```
=== "JS agent"
```json title="langgraph.json"
{
"node_version": "20",
"graphs": {
"agent": "./src/agent/index.ts:graph"
},
"ui": {
"agent": "./src/agent/ui.tsx"
}
}
```
```json
{
"node_version": "20",
"graphs": {
"agent": "./src/agent/index.ts:graph"
},
"ui": {
"agent": "./src/agent/ui.tsx"
}
}
```
The `ui` section points to the UI components that will be used by graphs. By default, we recommend using the same key as the graph name, but you can split out the components however you like, see [Customise the namespace of UI components](#customise-the-namespace-of-ui-components) for more details.
@@ -0,0 +1,184 @@
# Breakpoints
[Breakpoints](../../concepts/breakpoints.md) pause graph execution at defined points and let you step through each stage. They use LangGraph's [**persistence layer**](../../concepts/persistence.md), which saves the graph state after each step.
With breakpoints, you can inspect the graph's state and node inputs at any point. Execution pauses **indefinitely** until you resume, as the checkpointer preserves the state.
## Set breakpoints
=== "Compile time"
```python
# highlight-next-line
graph = graph_builder.compile( # (1)!
# highlight-next-line
interrupt_before=["node_a"], # (2)!
# highlight-next-line
interrupt_after=["node_b", "node_c"], # (3)!
)
```
1. The breakpoints are set during `compile` time.
2. `interrupt_before` specifies the nodes where execution should pause before the node is executed.
3. `interrupt_after` specifies the nodes where execution should pause after the node is executed.
=== "Run time"
=== "Python"
```python
# highlight-next-line
await client.runs.wait( # (1)!
thread_id,
assistant_id,
inputs=inputs,
# highlight-next-line
interrupt_before=["node_a"], # (2)!
# highlight-next-line
interrupt_after=["node_b", "node_c"] # (3)!
)
```
1. `client.runs.wait` is called with the `interrupt_before` and `interrupt_after` parameters. This is a run-time configuration and can be changed for every invocation.
2. `interrupt_before` specifies the nodes where execution should pause before the node is executed.
3. `interrupt_after` specifies the nodes where execution should pause after the node is executed.
=== "JavaScript"
```js
// highlight-next-line
await client.runs.wait( // (1)!
threadID,
assistantID,
{
input: input,
// highlight-next-line
interruptBefore: ["node_a"], // (2)!
// highlight-next-line
interruptAfter: ["node_b", "node_c"] // (3)!
}
)
```
1. `client.runs.wait` is called with the `interruptBefore` and `interruptAfter` parameters. This is a run-time configuration and can be changed for every invocation.
2. `interruptBefore` specifies the nodes where execution should pause before the node is executed.
3. `interruptAfter` specifies the nodes where execution should pause after the node is executed.
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"interrupt_before\": [\"node_a\"],
\"interrupt_after\": [\"node_b\", \"node_c\"],
\"input\": <INPUT>
}"
```
!!! tip
This example shows how to add **static** breakpoints. See [this guide](../../how-tos/human_in_the_loop/breakpoints.ipynb) for more options for how to add breakpoints.
=== "Python"
```python
from langgraph_sdk import get_client
client = get_client(url=<DEPLOYMENT_URL>)
# Using the graph deployed with the name "agent"
assistant_id = "agent"
# create a thread
thread = await client.threads.create()
thread_id = thread["thread_id"]
# Run the graph until the breakpoint
result = await client.runs.wait(
thread_id,
assistant_id,
input=inputs # (1)!
)
# Resume the graph
await client.runs.wait(
thread_id,
assistant_id,
input=None # (2)!
)
```
1. The graph is run until the first breakpoint is hit.
2. The graph is resumed by passing in `None` for the input. This will run the graph until the next breakpoint is hit.
=== "JavaScript"
```js
import { Client } from "@langchain/langgraph-sdk";
const client = new Client({ apiUrl: <DEPLOYMENT_URL> });
// Using the graph deployed with the name "agent"
const assistantID = "agent";
// create a thread
const thread = await client.threads.create();
const threadID = thread["thread_id"];
// Run the graph until the breakpoint
const result = await client.runs.wait(
threadID,
assistantID,
{ input: input } // (1)!
);
// Resume the graph
await client.runs.wait(
threadID,
assistantID,
{ input: null } // (2)!
);
```
1. The graph is run until the first breakpoint is hit.
2. The graph is resumed by passing in `null` for the input. This will run the graph until the next breakpoint is hit.
=== "cURL"
Create a thread:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads \
--header 'Content-Type: application/json' \
--data '{}'
```
Run the graph until the breakpoint:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"input\": <INPUT>
}"
```
Resume the graph:
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/wait \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\"
}"
```
## Learn more
- [**LangGraph breakpoints guide**](../../how-tos/human_in_the_loop/breakpoints.ipynb): learn more about adding breakpoints in LangGraph.
@@ -0,0 +1,549 @@
# How to review tool calls
!!! tip "Prerequisites"
This guide assumes familiarity with the following concepts:
* [Tool calling](https://python.langchain.com/docs/concepts/tool_calling/)
* [Human-in-the-loop](../../concepts/human_in_the_loop.md)
* [LangGraph Glossary](../../concepts/low_level.md)
Human-in-the-loop (HIL) interactions are crucial for [agentic systems](../../concepts/agentic_concepts.md). A common pattern is to add some human in the loop step after certain tool calls. These tool calls often lead to either a function call or saving of some information. Examples include:
- A tool call to execute SQL, which will then be run by the tool
- A tool call to generate a summary, which will then be saved to the State of the graph
Note that using tool calls is common **whether actually calling tools or not**.
There are typically a few different interactions you may want to do here:
1. Approve the tool call and continue
2. Modify the tool call manually and then continue
3. Give natural language feedback, and then pass that back to the agent
We can implement these in LangGraph using the [`interrupt()`][langgraph.types.interrupt] function. `interrupt` allows us to stop graph execution to collect input from a user and continue execution with collected input:
```python
def human_review_node(state) -> Command[Literal["call_llm", "run_tool"]]:
# this is the value we'll be providing via Command(resume=<human_review>)
human_review = interrupt(
{
"question": "Is this correct?",
# Surface tool calls for review
"tool_call": tool_call
}
)
review_action, review_data = human_review
# Approve the tool call and continue
if review_action == "continue":
return Command(goto="run_tool")
# Modify the tool call manually and then continue
elif review_action == "update":
...
updated_msg = get_updated_msg(review_data)
return Command(goto="run_tool", update={"messages": [updated_message]})
# Give natural language feedback, and then pass that back to the agent
elif review_action == "feedback":
...
feedback_msg = get_feedback_msg(review_data)
return Command(goto="call_llm", update={"messages": [feedback_msg]})
```
## Setup
We are not going to show the full code for the graph we are hosting, but you can see it [here](../../how-tos/human_in_the_loop/review-tool-calls.ipynb). Once this graph is hosted, we are ready to invoke it and wait for user input.
### SDK initialization
First, we need to setup our client so that we can communicate with our hosted graph:
=== "Python"
```python
from langgraph_sdk import get_client
client = get_client(url=<DEPLOYMENT_URL>)
# Using the graph deployed with the name "agent"
assistant_id = "agent"
thread = await client.threads.create()
```
=== "Javascript"
```js
import { Client } from "@langchain/langgraph-sdk";
const client = new Client({ apiUrl: <DEPLOYMENT_URL> });
// Using the graph deployed with the name "agent"
const assistantId = "agent";
const thread = await client.threads.create();
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads \
--header 'Content-Type: application/json' \
--data '{}'
```
## Example of approving tool
First, let's run the agent with an input that requires tool calls with approval:
=== "Python"
```python
input = {"messages": [{"role": "user", "content": "what's the weather in sf?"}]}
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
input=input,
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const input = { "messages": [{ "role": "user", "content": "what's the weather in sf?" }] };
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
input: input,
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"input\": {\"messages\": [{\"role\": \"human\", \"content\": \"what's the weather in sf?\"}]},
\"stream_mode\": [
\"updates\"
]
}"
```
Output:
{'call_llm': {'messages': [{'content': [{'text': "I'll help you check the weather in San Francisco.", 'type': 'text'}, {'id': 'toolu_01142G3woscA8JjFTLdqymtn', 'input': {'city': 'San Francisco'}, 'name': 'weather_search', 'type': 'tool_use'}], 'additional_kwargs': {}, 'response_metadata': {'id': 'msg_01Tdfufy4nZYXMbVZvgyNbhc', 'model': 'claude-3-5-sonnet-20241022', 'stop_reason': 'tool_use', 'stop_sequence': None, 'usage': {'cache_creation_input_tokens': 0, 'cache_read_input_tokens': 0, 'input_tokens': 379, 'output_tokens': 66}, 'model_name': 'claude-3-5-sonnet-20241022'}, 'type': 'ai', 'name': None, 'id': 'run-a33434b2-f5ca-40c6-98e2-6288d349d4ce-0', 'example': False, 'tool_calls': [{'name': 'weather_search', 'args': {'city': 'San Francisco'}, 'id': 'toolu_01142G3woscA8JjFTLdqymtn', 'type': 'tool_call'}], 'invalid_tool_calls': [], 'usage_metadata': {'input_tokens': 379, 'output_tokens': 66, 'total_tokens': 445, 'input_token_details': {'cache_read': 0, 'cache_creation': 0}}}]}}
{'__interrupt__': [{'value': {'question': 'Is this correct?', 'tool_call': {'name': 'weather_search', 'args': {'city': 'San Francisco'}, 'id': 'toolu_01142G3woscA8JjFTLdqymtn', 'type': 'tool_call'}}, 'resumable': True, 'ns': ['human_review_node:9caf42cf-1371-7213-a331-e6fe5d026be8'], 'when': 'during'}]}
To approve the tool call, we need to let `human_review_node` know what value to use for the `human_review` variable we defined inside the node. We can provide this value by invoking the graph with a `Command(resume=<human_review>)` input. Since we're approving the tool call, we'll provide `resume` value of `{"action": "continue"}` to navigate to `run_tool` node:
=== "Python"
```python
# highlight-next-line
from langgraph_sdk.schema import Command
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
# highlight-next-line
command=Command(resume={"action": "continue"}),
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
// highlight-next-line
command: { resume: { "action": "continue" } },
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"command\": {
\"resume\": { \"action\": \"continue\"}
},
\"stream_mode\": [
\"updates\"
]
}"
```
Output:
{'human_review_node': None}
{'run_tool': {'messages': [{'role': 'tool', 'name': 'weather_search', 'content': 'Sunny!', 'tool_call_id': 'toolu_01142G3woscA8JjFTLdqymtn'}]}}
{'call_llm': {'messages': [{'content': "According to the search, it's sunny in San Francisco right now!", 'additional_kwargs': {}, 'response_metadata': {'id': 'msg_01JJE9AtT4a9Lob91RRiW9rU', 'model': 'claude-3-5-sonnet-20241022', 'stop_reason': 'end_turn', 'stop_sequence': None, 'usage': {'cache_creation_input_tokens': 0, 'cache_read_input_tokens': 0, 'input_tokens': 458, 'output_tokens': 18}, 'model_name': 'claude-3-5-sonnet-20241022'}, 'type': 'ai', 'name': None, 'id': 'run-5e8d80b5-c46a-4aad-af37-b01f8bb15963-0', 'example': False, 'tool_calls': [], 'invalid_tool_calls': [], 'usage_metadata': {'input_tokens': 458, 'output_tokens': 18, 'total_tokens': 476, 'input_token_details': {'cache_read': 0, 'cache_creation': 0}}}]}}
## Edit Tool Call
Let's now say we want to edit the tool call. E.g. change some of the parameters (or even the tool called!) but then execute that tool.
=== "Python"
```python
input = {"messages": [{"role": "user", "content": "what's the weather in sf?"}]}
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
input=input,
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const input = { "messages": [{ "role": "user", "content": "what's the weather in sf?" }] };
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
input: input,
streamMode: "updates",
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"input\": {\"messages\": [{\"role\": \"human\", \"content\": \"what's the weather in sf?\"}]},
\"stream_mode\": [
\"updates\"
]
}"
```
To do this, we will use `Command` with a different resume value of `{"action": "update", "data": <tool call args>}`. This will do the following:
* combine existing tool call with user-provided tool call arguments and update the existing AI message with the new tool call
* navigate to `run_tool` node with the updated AI message and continue execution
=== "Python"
```python
# highlight-next-line
from langgraph_sdk.schema import Command
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
# highlight-next-line
command=Command(
# highlight-next-line
resume={"action": "update", "data": {"city": "San Francisco, USA"}}
# highlight-next-line
),
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
// highlight-next-line
command: {
// highlight-next-line
resume: { "action": "update", "data": { "city": "San Francisco, USA" } }
// highlight-next-line
},
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"command\": {
\"resume\": { \"action\": \"update\", \"data\": { \"city\": \"San Francisco, USA\" } }
},
\"stream_mode\": [
\"updates\"
]
}"
```
Output:
{'human_review_node': {'messages': [{'role': 'ai', 'content': [{'text': "I'll help you check the weather in San Francisco.", 'type': 'text'}, {'id': 'toolu_016L4EDPcaQRzzZxiB4Wq2wa', 'input': {'city': 'San Francisco'}, 'name': 'weather_search', 'type': 'tool_use'}], 'tool_calls': [{'id': 'toolu_016L4EDPcaQRzzZxiB4Wq2wa', 'name': 'weather_search', 'args': {'city': 'San Francisco, USA'}}], 'id': 'run-b07f0c35-4e93-43a5-9b48-363767ada3ca-0'}]}}
{'run_tool': {'messages': [{'role': 'tool', 'name': 'weather_search', 'content': 'Sunny!', 'tool_call_id': 'toolu_016L4EDPcaQRzzZxiB4Wq2wa'}]}}
{'call_llm': {'messages': [{'content': "According to the search, it's sunny in San Francisco right now!", 'additional_kwargs': {}, 'response_metadata': {'id': 'msg_01De5HurjNUMwMUpfRtMLbX1', 'model': 'claude-3-5-sonnet-20241022', 'stop_reason': 'end_turn', 'stop_sequence': None, 'usage': {'cache_creation_input_tokens': 0, 'cache_read_input_tokens': 0, 'input_tokens': 460, 'output_tokens': 18}, 'model_name': 'claude-3-5-sonnet-20241022'}, 'type': 'ai', 'name': None, 'id': 'run-85e2aaaa-6f61-4fa0-b594-b6e57129d7e7-0', 'example': False, 'tool_calls': [], 'invalid_tool_calls': [], 'usage_metadata': {'input_tokens': 460, 'output_tokens': 18, 'total_tokens': 478, 'input_token_details': {'cache_read': 0, 'cache_creation': 0}}}]}}
## Give feedback to a tool call
Sometimes, you may not want to execute a tool call, but you also may not want to ask the user to manually modify the tool call. In that case it may be better to get natural language feedback from the user. You can then insert this feedback as a mock **RESULT** of the tool call.
There are multiple ways to do this:
1. You could add a new message to the state (representing the "result" of a tool call)
2. You could add TWO new messages to the state - one representing an "error" from the tool call, other HumanMessage representing the feedback
Both are similar in that they involve adding messages to the state. The main difference lies in the logic AFTER the `human_review_node` and how it handles different types of messages.
For this example we will just add a single tool call representing the feedback (see `human_review_node` implementation). Let's see this in action!
=== "Python"
```python
input = {"messages": [{"role": "user", "content": "what's the weather in sf?"}]}
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
input=input,
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const input = { "messages": [{ "role": "user", "content": "what's the weather in sf?" }] };
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
input: input,
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"input\": {\"messages\": [{\"role\": \"human\", \"content\": \"what's the weather in sf?\"}]},
\"stream_mode\": [
\"updates\"
]
}"
```
To do this, we will use `Command` with a different resume value of `{"action": "feedback", "data": <feedback string>}`. This will do the following:
* create a new tool message that combines existing tool call from LLM with the with user-provided feedback as content
* navigate to `call_llm` node with the updated tool message and continue execution
=== "Python"
```python
# highlight-next-line
from langgraph_sdk.schema import Command
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
# highlight-next-line
command=Command(
resume={
"action": "feedback",
"data": "User requested changes: use <city, country> format for location"
}
),
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
// highlight-next-line
command: {
resume: {
"action": "feedback",
"data": "User requested changes: use <city, country> format for location"
}
},
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"command\": {
\"resume\": { \"action\": \"feedback\", \"data\": \"User requested changes: use <city, country> format for location\" }
},
\"stream_mode\": [
\"updates\"
]
}"
```
Output:
{'human_review_node': {'messages': [{'role': 'tool', 'content': 'User requested changes: use <city, country> format for location', 'name': 'weather_search', 'tool_call_id': 'toolu_01RkPHCjpfoUvPAktaq4Cqhm'}]}}
{'call_llm': {'messages': [{'content': [{'text': 'Let me try that again with the correct format:', 'type': 'text'}, {'id': 'toolu_01Rdrag6cVufHZG26BwVaiE7', 'input': {'city': 'San Francisco, USA'}, 'name': 'weather_search', 'type': 'tool_use'}], 'additional_kwargs': {}, 'response_metadata': {'id': 'msg_01EBan969yY5f6iGk6sPgKcj', 'model': 'claude-3-5-sonnet-20241022', 'stop_reason': 'tool_use', 'stop_sequence': None, 'usage': {'cache_creation_input_tokens': 0, 'cache_read_input_tokens': 0, 'input_tokens': 469, 'output_tokens': 68}, 'model_name': 'claude-3-5-sonnet-20241022'}, 'type': 'ai', 'name': None, 'id': 'run-64bbc255-d126-4db0-8ae5-3197cf29bed1-0', 'example': False, 'tool_calls': [{'name': 'weather_search', 'args': {'city': 'San Francisco, USA'}, 'id': 'toolu_01Rdrag6cVufHZG26BwVaiE7', 'type': 'tool_call'}], 'invalid_tool_calls': [], 'usage_metadata': {'input_tokens': 469, 'output_tokens': 68, 'total_tokens': 537, 'input_token_details': {'cache_read': 0, 'cache_creation': 0}}}]}}
{'__interrupt__': [{'value': {'question': 'Is this correct?', 'tool_call': {'name': 'weather_search', 'args': {'city': 'San Francisco, USA'}, 'id': 'toolu_01Rdrag6cVufHZG26BwVaiE7', 'type': 'tool_call'}}, 'resumable': True, 'ns': ['human_review_node:e9856878-e28c-5dd1-d353-4d83aa1a3a2b'], 'when': 'during'}]}
We can see that we now get to another interrupt - because it went back to the model and got an entirely new prediction of what to call. Let's now approve this one and continue.
=== "Python"
```python
# highlight-next-line
from langgraph_sdk.schema import Command
async for chunk in client.runs.stream(
thread["thread_id"],
assistant_id,
# highlight-next-line
command=Command(resume={"action": "continue"}),
stream_mode="updates",
):
if chunk.data and chunk.event != "metadata":
print(chunk.data)
```
=== "Javascript"
```js
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantId,
{
// highlight-next-line
command: { resume: { "action": "continue" } },
streamMode: "updates"
}
);
for await (const chunk of streamResponse) {
if (chunk.data && chunk.event !== "metadata") {
console.log(chunk.data);
}
}
```
=== "cURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data "{
\"assistant_id\": \"agent\",
\"command\": {
\"resume\": { \"action\": \"continue\"}
},
\"stream_mode\": [
\"updates\"
]
}"
```
Output:
{'human_review_node': None}
{'run_tool': {'messages': [{'role': 'tool', 'name': 'weather_search', 'content': 'Sunny!', 'tool_call_id': 'toolu_01Rdrag6cVufHZG26BwVaiE7'}]}}
{'call_llm': {'messages': [{'content': 'The weather in San Francisco is sunny!', 'additional_kwargs': {}, 'response_metadata': {'id': 'msg_013WTDHhbg8WiYLiQ9n2CaTk', 'model': 'claude-3-5-sonnet-20241022', 'stop_reason': 'end_turn', 'stop_sequence': None, 'usage': {'cache_creation_input_tokens': 0, 'cache_read_input_tokens': 0, 'input_tokens': 550, 'output_tokens': 12}, 'model_name': 'claude-3-5-sonnet-20241022'}, 'type': 'ai', 'name': None, 'id': 'run-b6c815f0-989a-47cf-b150-33e3bbc4eab7-0', 'example': False, 'tool_calls': [], 'invalid_tool_calls': [], 'usage_metadata': {'input_tokens': 550, 'output_tokens': 12, 'total_tokens': 562, 'input_token_details': {'cache_read': 0, 'cache_creation': 0}}}]}}
@@ -1,8 +1,10 @@
# Time travel using Server API
# Time travel
LangGraph provides the [**time travel**](../../concepts/time-travel.md) functionality to resume execution from a prior checkpoint, either replaying the same state or modifying it to explore alternatives. In all cases, resuming past execution produces a new fork in the history.
LangGraph provides [**time travel**](../../concepts/time-travel.md) functionality to **resume execution from a prior checkpoint** either replaying the same state or modifying it to explore alternatives. In all cases, resuming past execution produces a **new fork** in the history.
To time travel using the LangGraph Server API (via the LangGraph SDK):
## Use time travel
To use time-travel in LangGraph:
1. **Run the graph** with initial inputs using [LangGraph SDK](https://langchain-ai.github.io/langgraph/cloud/reference/sdk/python_sdk_ref/)'s [`client.runs.wait`][langgraph_sdk.client.RunsClient.wait] or [`client.runs.stream`][langgraph_sdk.client.RunsClient.stream] APIs.
2. **Identify a checkpoint in an existing thread**: Use [`client.threads.get_history`][langgraph_sdk.client.ThreadsClient.get_history] method to retrieve the execution history for a specific `thread_id` and locate the desired `checkpoint_id`.
@@ -10,7 +12,7 @@ To time travel using the LangGraph Server API (via the LangGraph SDK):
3. **(Optional) modify the graph state**: Use the [`client.threads.update_state`][langgraph_sdk.client.ThreadsClient.update_state] method to modify the graphs state at the checkpoint and resume execution from alternative state.
4. **Resume execution from the checkpoint**: Use the [`client.runs.wait`][langgraph_sdk.client.RunsClient.wait] or [`client.runs.stream`][langgraph_sdk.client.RunsClient.stream] APIs with an input of `None` and the appropriate `thread_id` and `checkpoint_id`.
## Use time travel in a workflow
## Example
??? example "Example graph"
@@ -235,4 +237,4 @@ To time travel using the LangGraph Server API (via the LangGraph SDK):
## Learn more
- [**LangGraph time travel guide**](../../how-tos/human_in_the_loop/time-travel.md): learn more about using time travel in LangGraph.
- [**LangGraph time travel guide**](../../how-tos/human_in_the_loop/time-travel.ipynb): learn more about using time travel in LangGraph.
@@ -247,7 +247,5 @@ Verify that the original, interrupted run was interrupted
Output:
```
'interrupted'
```
+3 -3
View File
@@ -3,7 +3,7 @@
!!!info "Prerequisites"
- [Running agents](../../agents/run_agents.md#running-agents)
This guide shows how to submit a [run](../../concepts/assistants.md#execution) to your application.
This guide shows how to submit a [run](../concepts/runs.md) to your application.
## Graph mode
@@ -29,11 +29,11 @@ Click the dropdown next to "Submit" and click the toggle to enable/disable strea
To run your graph with breakpoints, click the "Interrupt" button. Select a node and whether to pause before and/or after that node has executed. Click "Continue" in the thread log to resume execution.
For more information on breakpoints see [here](../../concepts/human_in_the_loop.md).
For more information on breakpoints see [here](../../concepts/breakpoints.md).
### Submit run
To submit the run with the specified input and run settings, click the "Submit" button. This will add a [run](../../concepts/assistants.md#execution) to the existing selected [thread](../../concepts/persistence.md#threads). If no thread is currently selected, a new one will be created.
To submit the run with the specified input and run settings, click the "Submit" button. This will add a [run](../concepts/runs.md) to the existing selected [thread](../../concepts/persistence.md#threads). If no thread is currently selected, a new one will be created.
To cancel the ongoing run, click the "Cancel" button.
+7 -14
View File
@@ -73,11 +73,9 @@ langgraph dev --debug-port 5678
Then attach your preferred debugger:
=== "VS Code"
Add this configuration to `launch.json`:
```json
{
Add this configuration to `launch.json`:
`json
{
"name": "Attach to LangGraph",
"type": "debugpy",
"request": "attach",
@@ -85,16 +83,11 @@ Then attach your preferred debugger:
"host": "0.0.0.0",
"port": 5678
}
}
```
}
`
Specify the port number you chose in the previous step.
=== "PyCharm"
1. Go to Run → Edit Configurations
2. Click + and select "Python Debug Server"
3. Set IDE host name: `localhost`
4. Set port: `5678` (or the port number you chose in the previous step)
5. Click "OK" and start debugging
=== "PyCharm" 1. Go to Run → Edit Configurations 2. Click + and select "Python Debug Server" 3. Set IDE host name: `localhost` 4. Set port: `5678` (or the port number you chose in the previous step) 5. Click "OK" and start debugging
## Troubleshooting
+1 -69
View File
@@ -1,4 +1,4 @@
# How to integrate LangGraph into your React application
How to integrate LangGraph into your React application# How to integrate LangGraph into your React application
!!! info "Prerequisites"
@@ -503,74 +503,6 @@ const handleSubmit = (text: string) => {
};
```
### Cached Thread Display
Use the `initialValues` option to display cached thread data immediately while the history is being loaded from the server. This improves user experience by showing cached data instantly when navigating to existing threads.
```tsx
import { useStream } from "@langchain/langgraph-sdk/react";
const CachedThreadExample = ({ threadId, cachedThreadData }) => {
const stream = useStream({
apiUrl: "http://localhost:2024",
assistantId: "agent",
threadId,
// Show cached data immediately while history loads
initialValues: cachedThreadData?.values,
messagesKey: "messages",
});
return (
<div>
{stream.messages.map((message) => (
<div key={message.id}>{message.content as string}</div>
))}
</div>
);
};
```
### Optimistic Thread Creation
Use the `threadId` option in `submit` function to enable optimistic UI patterns where you need to know the thread ID before the thread is actually created.
```tsx
import { useState } from "react";
import { useStream } from "@langchain/langgraph-sdk/react";
const OptimisticThreadExample = () => {
const [threadId, setThreadId] = useState<string | null>(null);
const [optimisticThreadId] = useState(() => crypto.randomUUID());
const stream = useStream({
apiUrl: "http://localhost:2024",
assistantId: "agent",
threadId,
onThreadId: setThreadId, // (3) Updated after thread has been created.
messagesKey: "messages",
});
const handleSubmit = (text: string) => {
// (1) Perform a soft navigation to /threads/${optimisticThreadId}
// without waiting for thread creation.
window.history.pushState({}, "", `/threads/${optimisticThreadId}`);
// (2) Submit message to create thread with the predetermined ID.
stream.submit(
{ messages: [{ type: "human", content: text }] },
{ threadId: optimisticThreadId }
);
};
return (
<div>
<p>Thread ID: {threadId ?? optimisticThreadId}</p>
{/* Rest of component */}
</div>
);
};
```
### TypeScript
The `useStream()` hook is friendly for apps written in TypeScript and you can specify types for the state to get better type safety and IDE support.
+69 -91
View File
@@ -8,15 +8,15 @@ Currently, the SDK does not provide built-in support for defining webhook endpoi
The following API endpoints accept a `webhook` parameter:
| Operation | HTTP Method | Endpoint |
|----------------------|-------------|-----------------------------------|
| Create Run | `POST` | `/thread/{thread_id}/runs` |
| Create Thread Cron | `POST` | `/thread/{thread_id}/runs/crons` |
| Stream Run | `POST` | `/thread/{thread_id}/runs/stream` |
| Wait Run | `POST` | `/thread/{thread_id}/runs/wait` |
| Create Cron | `POST` | `/runs/crons` |
| Stream Run Stateless | `POST` | `/runs/stream` |
| Wait Run Stateless | `POST` | `/runs/wait` |
| Operation | HTTP Method | Endpoint |
|-----------|------------|----------|
| Create Run | `POST` | `/thread/{thread_id}/runs` |
| Create Thread Cron | `POST` | `/thread/{thread_id}/runs/crons` |
| Stream Run | `POST` | `/thread/{thread_id}/runs/stream` |
| Wait Run | `POST` | `/thread/{thread_id}/runs/wait` |
| Create Cron | `POST` | `/runs/crons` |
| Stream Run Stateless | `POST` | `/runs/stream` |
| Wait Run Stateless | `POST` | `/runs/wait` |
In this guide, well show how to trigger a webhook after streaming a run.
@@ -25,39 +25,36 @@ In this guide, well show how to trigger a webhook after streaming a run.
Before making API calls, set up your assistant and thread.
=== "Python"
```python
from langgraph_sdk import get_client
```python
from langgraph_sdk import get_client
client = get_client(url=<DEPLOYMENT_URL>)
assistant_id = "agent"
thread = await client.threads.create()
print(thread)
```
client = get_client(url=<DEPLOYMENT_URL>)
assistant_id = "agent"
thread = await client.threads.create()
print(thread)
```
=== "JavaScript"
```js
import { Client } from "@langchain/langgraph-sdk";
```js
import { Client } from "@langchain/langgraph-sdk";
const client = new Client({ apiUrl: <DEPLOYMENT_URL> });
const assistantID = "agent";
const thread = await client.threads.create();
console.log(thread);
```
const client = new Client({ apiUrl: <DEPLOYMENT_URL> });
const assistantID = "agent";
const thread = await client.threads.create();
console.log(thread);
```
=== "CURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/assistants/search \
--header 'Content-Type: application/json' \
--data '{ "limit": 10, "offset": 0 }' | jq -c 'map(select(.config == null or .config == {})) | .[0]' && \
curl --request POST \
--url <DEPLOYMENT_URL>/threads \
--header 'Content-Type: application/json' \
--data '{}'
```
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/assistants/search \
--header 'Content-Type: application/json' \
--data '{ "limit": 10, "offset": 0 }' | jq -c 'map(select(.config == null or .config == {})) | .[0]' && \
curl --request POST \
--url <DEPLOYMENT_URL>/threads \
--header 'Content-Type: application/json' \
--data '{}'
```
Example response:
@@ -80,55 +77,52 @@ To use a webhook, specify the `webhook` parameter in your API request. When the
For example, if your server listens for webhook events at `https://my-server.app/my-webhook-endpoint`, include this in your request:
=== "Python"
```python
input = { "messages": [{ "role": "user", "content": "Hello!" }] }
```python
input = { "messages": [{ "role": "user", "content": "Hello!" }] }
async for chunk in client.runs.stream(
thread_id=thread["thread_id"],
assistant_id=assistant_id,
input=input,
stream_mode="events",
webhook="https://my-server.app/my-webhook-endpoint"
):
pass
```
async for chunk in client.runs.stream(
thread_id=thread["thread_id"],
assistant_id=assistant_id,
input=input,
stream_mode="events",
webhook="https://my-server.app/my-webhook-endpoint"
):
pass
```
=== "JavaScript"
```js
const input = { messages: [{ role: "human", content: "Hello!" }] };
```js
const input = { messages: [{ role: "human", content: "Hello!" }] };
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantID,
{
input: input,
webhook: "https://my-server.app/my-webhook-endpoint"
}
);
const streamResponse = client.runs.stream(
thread["thread_id"],
assistantID,
{
input: input,
webhook: "https://my-server.app/my-webhook-endpoint"
}
);
for await (const chunk of streamResponse) {
// Handle stream output
}
```
for await (const chunk of streamResponse) {
// Handle stream output
}
```
=== "CURL"
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data '{
"assistant_id": <ASSISTANT_ID>,
"input": {"messages": [{"role": "user", "content": "Hello!"}]},
"webhook": "https://my-server.app/my-webhook-endpoint"
}'
```
```bash
curl --request POST \
--url <DEPLOYMENT_URL>/threads/<THREAD_ID>/runs/stream \
--header 'Content-Type: application/json' \
--data '{
"assistant_id": <ASSISTANT_ID>,
"input": {"messages": [{"role": "user", "content": "Hello!"}]},
"webhook": "https://my-server.app/my-webhook-endpoint"
}'
```
## Webhook payload
LangGraph Platform sends webhook notifications in the format of a [Run](../../concepts/assistants.md#execution). See the [API Reference](https://langchain-ai.github.io/langgraph/cloud/reference/api/api_ref.html#model/run) for details. The request payload includes run input, configuration, and other metadata in the `kwargs` field.
LangGraph Platform sends webhook notifications in the format of a [Run](../../cloud/concepts/runs.md). See the [API Reference](https://langchain-ai.github.io/langgraph/cloud/reference/api/api_ref.html#model/run) for details. The request payload includes run input, configuration, and other metadata in the `kwargs` field.
## Secure webhooks
@@ -140,22 +134,6 @@ https://my-server.app/my-webhook-endpoint?token=YOUR_SECRET_TOKEN
Your server should extract and validate this token before processing requests.
## Disable webhooks
As of `langgraph-api>=0.2.78`, developers can disable webhooks in the `langgraph.json` file:
```json
{
"http": {
"disable_webhooks": true
}
}
```
This feature is primarily intended for self-hosted deployments, where platform administrators or developers may prefer to disable webhooks to simplify their security posture—especially if they are not configuring firewall rules or other network controls. Disabling webhooks helps prevent untrusted payloads from being sent to internal endpoints.
For full configuration details, refer to the [configuration file reference](https://langchain-ai.github.io/langgraph/cloud/reference/cli/?h=disable_webhooks#configuration-file).
## Test webhooks
You can test your webhook using online services like:
+1 -2
View File
@@ -154,9 +154,8 @@ You can now test the API:
```bash
curl -s --request POST \
--url <DEPLOYMENT_URL>/runs/stream \
--url <DEPLOYMENT_URL> \
--header 'Content-Type: application/json' \
--header "X-Api-Key: <LANGSMITH API KEY> \
--data "{
\"assistant_id\": \"agent\",
\"input\": {
+4 -4
View File
@@ -1,12 +1,12 @@
# LangGraph Server API Reference
# API Reference
The LangGraph Server API reference is available within each deployment at the `/docs` endpoint (e.g. `http://localhost:8124/docs`).
The LangGraph Platform API reference is available with each deployment at the `/docs` URL path (e.g. `http://localhost:8124/docs`).
Click <a href="/langgraph/cloud/reference/api/api_ref.html" target="_blank">here</a> to view the API reference.
## Authentication
For deployments to LangGraph Platform, authentication is required. Pass the `X-Api-Key` header with each request to the LangGraph Server. The value of the header should be set to a valid LangSmith API key for the organization where the LangGraph Server is deployed.
For deployments to LangGraph Platform, authentication is required. Pass the `X-Api-Key` header with each request to the LangGraph Platform API. The value of the header should be set to a valid LangSmith API key for the organization where the API is deployed.
Example `curl` command:
```shell
@@ -18,5 +18,5 @@ curl --request POST \
"metadata": {},
"limit": 10,
"offset": 0
}'
}'
```
@@ -1,247 +0,0 @@
# LangGraph Control Plane API Reference
The LangGraph Control Plane API is used to programmatically create and manage LangGraph Server deployments. For example, the APIs can be orchestrated to create custom CI/CD workflows.
Click <a href="https://api.host.langchain.com/docs" target="_blank">here</a> to view the API reference.
## Host
LangGraph Control Plane hosts for Cloud SaaS data regions:
| US | EU |
|----|----|
| `https://api.host.langchain.com` | `https://eu.api.host.langchain.com` |
**Note**: Self-hosted deployments of LangGraph Platform will have a custom host for the LangGraph Control Plane.
## Authentication
To authenticate with the LangGraph Control Plane API, set the `X-Api-Key` header to a valid LangSmith API key.
Example `curl` command:
```shell
curl --request GET \
--url http://localhost:8124/v2/deployments \
--header 'X-Api-Key: LANGSMITH_API_KEY'
```
## Versioning
Each endpoint path is prefixed with a version (e.g. `v1`, `v2`).
## Quick Start
1. Call `POST /v2/deployments` to create a new Deployment. The response body contains the Deployment ID (`id`) and the ID of the latest (and first) revision (`latest_revision_id`).
1. Call `GET /v2/deployments/{deployment_id}` to retrieve the Deployment. Set `deployment_id` in the URL to the value of Deployment ID (`id`).
1. Poll for revision `status` until `status` is `DEPLOYED` by calling `GET /v2/deployments/{deployment_id}/revisions/{latest_revision_id}`.
1. Call `PATCH /v2/deployments/{deployment_id}` to update the deployment.
## Example Code
Below is example Python code that demonstrates how to orchestrate the LangGraph Control Plane APIs to create a deployment, update the deployment, and delete the deployment.
```python
import os
import time
import requests
from dotenv import load_dotenv
load_dotenv()
# required environment variables
CONTROL_PLANE_HOST = os.getenv("CONTROL_PLANE_HOST")
LANGSMITH_API_KEY = os.getenv("LANGSMITH_API_KEY")
INTEGRATION_ID = os.getenv("INTEGRATION_ID")
MAX_WAIT_TIME = 1800 # 30 mins
def get_headers() -> dict:
"""Return common headers for requests to LangGraph Control Plane API."""
return {
"X-Api-Key": LANGSMITH_API_KEY,
}
def create_deployment() -> str:
"""Create deployment. Return deployment ID."""
headers = get_headers()
headers["Content-Type"] = "application/json"
deployment_name = "my_deployment"
request_body = {
"name": deployment_name,
"source": "github",
"source_config": {
"integration_id": INTEGRATION_ID,
"repo_url": "https://github.com/langchain-ai/langgraph-example",
"deployment_type": "dev",
"build_on_push": False,
"custom_url": None,
"resource_spec": None,
},
"source_revision_config": {
"repo_ref": "main",
"langgraph_config_path": "langgraph.json",
"image_uri": None,
},
"secrets": [
{
"name": "OPENAI_API_KEY",
"value": "test_openai_api_key",
},
{
"name": "ANTHROPIC_API_KEY",
"value": "test_anthropic_api_key",
},
{
"name": "TAVILY_API_KEY",
"value": "test_tavily_api_key",
},
],
}
response = requests.post(
url=f"{CONTROL_PLANE_HOST}/v2/deployments",
headers=headers,
json=request_body,
)
if response.status_code != 201:
raise Exception(f"Failed to create deployment: {response.text}")
deployment_id = response.json()["id"]
print(f"Created deployment {deployment_name} ({deployment_id})")
return deployment_id
def get_deployment(deployment_id: str) -> dict:
"""Get deployment."""
response = requests.get(
url=f"{CONTROL_PLANE_HOST}/v2/deployments/{deployment_id}",
headers=get_headers(),
)
if response.status_code != 200:
raise Exception(f"Failed to get deployment ID {deployment_id}: {response.text}")
return response.json()
def list_revisions(deployment_id: str) -> list[dict]:
"""List revisions.
Return list is sorted by created_at in descending order (latest first).
"""
response = requests.get(
url=f"{CONTROL_PLANE_HOST}/v2/deployments/{deployment_id}/revisions",
headers=get_headers(),
)
if response.status_code != 200:
raise Exception(
f"Failed to list revisions for deployment ID {deployment_id}: {response.text}"
)
return response.json()
def get_revision(
deployment_id: str,
revision_id: str,
) -> dict:
"""Get revision."""
response = requests.get(
url=f"{CONTROL_PLANE_HOST}/v2/deployments/{deployment_id}/revisions/{revision_id}",
headers=get_headers(),
)
if response.status_code != 200:
raise Exception(f"Failed to get revision ID {revision_id}: {response.text}")
return response.json()
def patch_deployment(deployment_id: str) -> None:
"""Patch deployment."""
headers = get_headers()
headers["Content-Type"] = "application/json"
response = requests.patch(
url=f"{CONTROL_PLANE_HOST}/v2/deployments/{deployment_id}",
headers=headers,
json={
"source_config": {
"build_on_push": True,
},
"source_revision_config": {
"repo_ref": "main",
"langgraph_config_path": "langgraph.json",
},
},
)
if response.status_code != 200:
raise Exception(f"Failed to patch deployment: {response.text}")
print(f"Patched deployment ID {deployment_id}")
def wait_for_deployment(deployment_id: str, revision_id: str) -> None:
"""Wait for revision status to be DEPLOYED."""
start_time = time.time()
revision, status = None, None
while time.time() - start_time < MAX_WAIT_TIME:
revision = get_revision(deployment_id, revision_id)
status = revision["status"]
if status == "DEPLOYED":
break
elif "FAILED" in status:
raise Exception(f"Revision ID {revision_id} failed: {revision}")
print(f"Waiting for revision ID {revision_id} to be DEPLOYED...")
time.sleep(60)
if status != "DEPLOYED":
raise Exception(
f"Timeout waiting for revision ID {revision_id} to be DEPLOYED: {revision}"
)
def delete_deployment(deployment_id: str) -> None:
"""Delete deployment."""
response = requests.delete(
url=f"{CONTROL_PLANE_HOST}/v2/deployments/{deployment_id}",
headers=get_headers(),
)
if response.status_code != 204:
raise Exception(
f"Failed to delete deployment ID {deployment_id}: {response.text}"
)
print(f"Deployment ID {deployment_id} deleted")
if __name__ == "__main__":
# create deployment and get the latest revision
deployment_id = create_deployment()
revisions = list_revisions(deployment_id)
latest_revision = revisions["resources"][0]
latest_revision_id = latest_revision["id"]
# wait for latest revision to be DEPLOYED
wait_for_deployment(deployment_id, latest_revision_id)
# patch the deployment and get the latest revision
patch_deployment(deployment_id)
revisions = list_revisions(deployment_id)
latest_revision = revisions["resources"][0]
latest_revision_id = latest_revision["id"]
# wait for latest revision to be DEPLOYED
wait_for_deployment(deployment_id, latest_revision_id)
# delete the deployment
delete_deployment(deployment_id)
```
File diff suppressed because it is too large Load Diff
+8 -14
View File
@@ -50,11 +50,9 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
| <span style="white-space: nowrap;">`python_version`</span> | `3.11`, `3.12`, or `3.13`. Defaults to `3.11`. |
| <span style="white-space: nowrap;">`node_version`</span> | Specify `node_version: 20` to use LangGraph.js. |
| <span style="white-space: nowrap;">`pip_config_file`</span> | Path to `pip` config file. |
| <span style="white-space: nowrap;">`pip_installer`</span> | _(Added in v0.3)_ Optional. Python package installer selector. It can be set to `"auto"`, `"pip"`, or `"uv"`. From version&nbsp;0.3 onward the default strategy is to run `uv pip`, which typically delivers faster builds while remaining a drop-in replacement. In the uncommon situation where `uv` cannot handle your dependency graph or the structure of your `pyproject.toml`, specify `"pip"` here to revert to the earlier behaviour. |
| <span style="white-space: nowrap;">`keep_pkg_tools`</span> | _(Added in v0.3.4)_ Optional. Control whether to retain Python packaging tools (`pip`, `setuptools`, `wheel`) in the final image. Accepted values: <ul><li><code>true</code> : Keep all three tools (skip uninstall).</li><li><code>false</code> / omitted : Uninstall all three tools (default behaviour).</li><li><code>list[str]</code> : Names of tools <strong>to retain</strong>. Each value must be one of "pip", "setuptools", "wheel".</li></ul>. By default, all three tools are uninstalled. |
| <span style="white-space: nowrap;">`dockerfile_lines`</span> | Array of additional lines to add to Dockerfile following the import from parent image. |
| <span style="white-space: nowrap;">`checkpointer`</span> | Configuration for the checkpointer. Contains a `ttl` field which is an object with the following keys: <ul><li>`strategy`: How to handle expired checkpoints (e.g., `"delete"`).</li><li>`sweep_interval_minutes`: How often to check for expired checkpoints (integer).</li><li>`default_ttl`: Default time-to-live for checkpoints in **minutes** (integer). Defines how long checkpoints are kept before the specified strategy is applied.</li></ul> |
| <span style="white-space: nowrap;">`http`</span> | HTTP server configuration with the following fields: <ul><li>`app`: Path to custom Starlette/FastAPI app (e.g., `"./src/agent/webapp.py:app"`). See [custom routes guide](../../how-tos/http/custom_routes.md).</li><li>`cors`: CORS configuration with fields for `allow_origins`, `allow_methods`, `allow_headers`, etc.</li><li>`configurable_headers`: Define which request headers to exclude or include as a run's configurable values.</li><li>`disable_assistants`: Disable `/assistants` routes</li><li>`disable_mcp`: Disable `/mcp` routes</li><li>`disable_meta`: Disable `/ok`, `/info`, `/metrics`, and `/docs` routes</li><li>`disable_runs`: Disable `/runs` routes</li><li>`disable_store`: Disable `/store` routes</li><li>`disable_threads`: Disable `/threads` routes</li><li>`disable_ui`: Disable `/ui` routes</li><li>`disable_webhooks`: Disable webhooks calls on run completion in all routes</li><li>`mount_prefix`: Prefix for mounted routes (e.g., "/my-deployment/api")</li></ul> |
| <span style="white-space: nowrap;">`http`</span> | HTTP server configuration with the following fields: <ul><li>`app`: Path to custom Starlette/FastAPI app (e.g., `"./src/agent/webapp.py:app"`). See [custom routes guide](../../how-tos/http/custom_routes.md).</li><li>`disable_assistants`: Disable `/assistants` routes</li><li>`disable_threads`: Disable `/threads` routes</li><li>`disable_runs`: Disable `/runs` routes</li><li>`disable_store`: Disable `/store` routes</li><li>`disable_meta`: Disable `/ok`, `/info`, `/metrics`, and `/docs` routes</li><li>`cors`: CORS configuration with fields for `allow_origins`, `allow_methods`, `allow_headers`, etc.</li><li>`configurable_headers`: Define which request headers to exclude or include as a run's configurable values.</li></ul> |
=== "JS"
@@ -130,7 +128,7 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
- `cohere:embed-english-v3.0`: 1024
- `cohere:embed-english-light-v3.0`: 384
- `cohere:embed-multilingual-v3.0`: 1024
- `cohere:embed-multilingual-light-v3.0`: 384
- `cohere:embed-multilingual-light-v3.0`: 384
#### Semantic search with a custom embedding function
@@ -363,8 +361,8 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
**Options**
| Option | Default | Description |
| -------------------- | ---------------- | --------------------------------------------------------------------------------------------------------------- |
| Option | Default | Description |
| -------------------- | ---------------- | ---------------------------------------------------------------------------------------------------------------------------- |
| `--platform TEXT` | | Target platform(s) to build the Docker image for. Example: `langgraph build --platform linux/amd64,linux/arm64` |
| `-t, --tag TEXT` | | **Required**. Tag for the Docker image. Example: `langgraph build -t my-image` |
| `--pull / --no-pull` | `--pull` | Build with latest remote Docker image. Use `--no-pull` for running the LangGraph Platform API server with locally built images. |
@@ -383,8 +381,8 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
**Options**
| Option | Default | Description |
| -------------------- | ---------------- | --------------------------------------------------------------------------------------------------------------- |
| Option | Default | Description |
| -------------------- | ---------------- | ---------------------------------------------------------------------------------------------------------------------------- |
| `--platform TEXT` | | Target platform(s) to build the Docker image for. Example: `langgraph build --platform linux/amd64,linux/arm64` |
| `-t, --tag TEXT` | | **Required**. Tag for the Docker image. Example: `langgraph build -t my-image` |
| `--no-pull` | | Use locally built images. Defaults to `false` to build with latest remote Docker image. |
@@ -396,7 +394,7 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
=== "Python"
Start LangGraph API server. For local testing, requires a LangSmith API key with access to LangGraph Platform. Requires a license key for production use.
Start LangGraph API server. For local testing, requires a LangSmith API key with access to LangGraph Platform closed beta. Requires a license key for production use.
**Usage**
@@ -409,8 +407,6 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
| Option | Default | Description |
| ---------------------------- | ------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| `--wait` | | Wait for services to start before returning. Implies --detach |
| `--base-image TEXT` | `langchain/langgraph-api` | Base image to use for the LangGraph API server. Pin to specific versions using version tags. |
| `--image TEXT` | | Docker image to use for the langgraph-api service. If specified, skips building and uses this image directly. |
| `--postgres-uri TEXT` | Local database | Postgres URI to use for the database. |
| `--watch` | | Restart on file changes |
| `--debugger-base-url TEXT` | `http://127.0.0.1:[PORT]` | URL used by the debugger to access LangGraph API. |
@@ -425,7 +421,7 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
=== "JS"
Start LangGraph API server. For local testing, requires a LangSmith API key with access to LangGraph Platform. Requires a license key for production use.
Start LangGraph API server. For local testing, requires a LangSmith API key with access to LangGraph Platform closed beta. Requires a license key for production use.
**Usage**
@@ -438,8 +434,6 @@ The LangGraph CLI requires a JSON configuration file that follows this [schema](
| Option | Default | Description |
| ---------------------------------------------------------------------- | ------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| <span style="white-space: nowrap;">`--wait`</span> | | Wait for services to start before returning. Implies --detach |
| <span style="white-space: nowrap;">`--base-image TEXT`</span> | <span style="white-space: nowrap;">`langchain/langgraph-api`</span> | Base image to use for the LangGraph API server. Pin to specific versions using version tags. |
| <span style="white-space: nowrap;">`--image TEXT`</span> | | Docker image to use for the langgraph-api service. If specified, skips building and uses this image directly. |
| <span style="white-space: nowrap;">`--postgres-uri TEXT`</span> | Local database | Postgres URI to use for the database. |
| <span style="white-space: nowrap;">`--watch`</span> | | Restart on file changes |
| <span style="white-space: nowrap;">`-c, --config FILE`</span> | `langgraph.json` | Path to configuration file declaring dependencies, graphs and environment variables. |
+26 -42
View File
@@ -10,10 +10,6 @@ This environment variable should be set to `True` if the implementation of a gra
Defaults to `False`.
## `BG_JOB_SHUTDOWN_GRACE_PERIOD_SECS`
Specifies, in seconds, how long the server will wait for background jobs to finish after the queue receives a shutdown signal. After this period, the server will force termination. Defaults to `180` seconds. Set this to ensure jobs have enough time to complete cleanly during shutdown. Added in `langgraph-api==0.2.16`.
## `BG_JOB_TIMEOUT_SECS`
The timeout of a background run can be increased. However, the infrastructure for a Cloud SaaS deployment enforces a 1 hour timeout limit for API requests. This means the connection between client and server will timeout after 1 hour. This is not configurable.
@@ -22,15 +18,16 @@ A background run can execute for longer than 1 hour, but a client must reconnect
Defaults to `3600`.
## `BG_JOB_SHUTDOWN_GRACE_PERIOD_SECS`
Specifies, in seconds, how long the server will wait for background jobs to finish after the queue receives a shutdown signal. After this period, the server will force termination. Defaults to `3600` seconds. Set this to ensure jobs have enough time to complete cleanly during shutdown. Added in `langgraph-api==0.2.16`.
## `DD_API_KEY`
Specify `DD_API_KEY` (your [Datadog API Key](https://docs.datadoghq.com/account_management/api-app-keys/)) to automatically enable Datadog tracing for the deployment. Specify other [`DD_*` environment variables](https://ddtrace.readthedocs.io/en/stable/configuration.html) to configure the tracing instrumentation.
If `DD_API_KEY` is specified, the application process is wrapped in the [`ddtrace-run` command](https://ddtrace.readthedocs.io/en/stable/installation_quickstart.html). Other `DD_*` environment variables (e.g. `DD_SITE`, `DD_ENV`, `DD_SERVICE`, `DD_TRACE_ENABLED`) are typically needed to properly configure the tracing instrumentation. See [`DD_*` environment variables](https://ddtrace.readthedocs.io/en/stable/configuration.html) for more details.
!!! note
Enabling `DD_API_KEY` (and thus `ddtrace-run`) can override or interfere with other auto-instrumentation solutions (such as OpenTelemetry) that you may have instrumented into your application code.
## `LANGCHAIN_TRACING_SAMPLING_RATE`
Sampling rate for traces sent to LangSmith. Valid values: Any float between `0` and `1`.
@@ -43,14 +40,6 @@ Type of authentication for the LangGraph Server deployment. Valid values: `langs
For deployments to LangGraph Platform, this environment variable is set automatically. For local development or deployments where authentication is handled externally (e.g. self-hosted), set this environment variable to `noop`.
## `LANGGRAPH_POSTGRES_POOL_MAX_SIZE`
Beginning with langgraph-api version `0.2.12`, the maximum size of the Postgres connection pool (per replica) can be controlled using the `LANGGRAPH_POSTGRES_POOL_MAX_SIZE` environment variable. By setting this variable, you can determine the upper bound on the number of simultaneous connections the server will establish with the Postgres database.
For example, if a deployment is scaled up to 10 replicas and `LANGGRAPH_POSTGRES_POOL_MAX_SIZE` is configured to `150`, then up to `1500` connections to Postgres can be established. This is particularly useful for deployments where database resources are limited (or more available) or where you need to tune connection behavior for performance or scaling reasons.
Defaults to `150` connections.
## `LANGSMITH_RUNS_ENDPOINTS`
For deployments with [self-hosted LangSmith](https://docs.smith.langchain.com/self_hosting) only.
@@ -61,14 +50,11 @@ Set this environment variable to have a deployment send traces to a self-hosted
## `LANGSMITH_TRACING`
!!! info "Only for Self-Hosted Data Plane, Self-Hosted Control Plane, and Standalone Container"
Disabling LangSmith tracing is only available for [Self-Hosted Data Plane](../../concepts/langgraph_self_hosted_data_plane.md), [Self-Hosted Control Plane](../../concepts/langgraph_self_hosted_control_plane.md), and [Standalone Container](../../concepts/langgraph_standalone_container.md) deployments.
Set `LANGSMITH_TRACING` to `false` to disable tracing to LangSmith.
Defaults to `true`.
## `LOG_COLOR`
This is mainly relevant in the context of using the dev server via the `langgraph dev` command. Set `LOG_COLOR` to `true` to enable ANSI-colored console output when using the default console renderer. Disabling color output by setting this variable to `false` produces monochrome logs. Defaults to `true`.
## `LOG_LEVEL`
Configure [log level](https://docs.python.org/3/library/logging.html#logging-levels). Defaults to `INFO`.
@@ -77,14 +63,9 @@ Configure [log level](https://docs.python.org/3/library/logging.html#logging-lev
Set `LOG_JSON` to `true` to render all log messages as JSON objects using the configured `JSONRenderer`. This produces structured logs that can be easily parsed or ingested by log management systems. Defaults to `false`.
## `MOUNT_PREFIX`
## `LOG_COLOR`
!!! info "Only Allowed in Self-Hosted Deployments"
The `MOUNT_PREFIX` environment variable is only allowed in Self-Hosted Deployment models, LangGraph Platform SaaS will not allow this environment variable.
Set `MOUNT_PREFIX` to serve the LangGraph Server under a specific path prefix. This is useful for deployments where the server is behind a reverse proxy or load balancer that requires a specific path prefix.
For example, if the server is to be served under `https://example.com/langgraph`, set `MOUNT_PREFIX` to `/langgraph`.
This is mainly relevant in the context of using the dev server via the `langgraph dev` command. Set `LOG_COLOR` to `true` to enable ANSI-colored console output when using the default console renderer. Disabling color output by setting this variable to `false` produces monochrome logs. Defaults to `true`.
## `N_JOBS_PER_WORKER`
@@ -114,14 +95,16 @@ Database Connectivity:
- The custom Postgres instance must be accessible by the LangGraph Server. The user is responsible for ensuring connectivity.
## `REDIS_CLUSTER`
## `LANGGRAPH_POSTGRES_POOL_MAX_SIZE`
!!! info "Only Allowed in Self-Hosted Deployments"
Redis Cluster mode is only available in Self-Hosted Deployment models, LangGraph Platform SaaS will provision a redis instance for you by default.
Beginning with langgraph-api version `0.2.12`, the maximum size of the Postgres connection pool can be controlled using the `LANGGRAPH_POSTGRES_POOL_MAX_SIZE` environment variable. By setting this variable, you can determine the upper bound on the number of simultaneous connections the server will establish with the Postgres database. This is particularly useful for deployments where database resources are limited (or more available) or where you need to tune connection behavior for performance or scaling reasons. If not specified, the pool size defaults to 150 connections.
Set `REDIS_CLUSTER` to `True` to enable Redis Cluster mode. When enabled, the system will connect to Redis using cluster mode. This is useful when connecting to a Redis Cluster deployment.
## `REDIS_URI_CUSTOM`
Defaults to `False`.
!!! info "Only for Self-Hosted Data Plane and Self-Hosted Control Plane"
Custom Redis instances are only available for [Self-Hosted Data Plane](../../concepts/langgraph_self_hosted_data_plane.md) and [Self-Hosted Control Plane](../../concepts/langgraph_self_hosted_control_plane.md) deployments.
Specify `REDIS_URI_CUSTOM` to use a custom Redis instance. The value of `REDIS_URI_CUSTOM` must be a valid [Redis connection URI](https://redis-py.readthedocs.io/en/stable/connections.html#redis.Redis.from_url).
## `REDIS_KEY_PREFIX`
@@ -132,19 +115,20 @@ Specify a prefix for Redis keys. This allows multiple LangGraph Server instances
Defaults to `''`.
## `REDIS_URI_CUSTOM`
## `REDIS_CLUSTER`
!!! info "Only for Self-Hosted Data Plane and Self-Hosted Control Plane"
Custom Redis instances are only available for [Self-Hosted Data Plane](../../concepts/langgraph_self_hosted_data_plane.md) and [Self-Hosted Control Plane](../../concepts/langgraph_self_hosted_control_plane.md) deployments.
!!! info "Only Allowed in Self-Hosted Deployments"
Redis Cluster mode is only available in Self-Hosted Deployment models, LangGraph Platform SaaS will provision a redis instance for you by default.
Specify `REDIS_URI_CUSTOM` to use a custom Redis instance. The value of `REDIS_URI_CUSTOM` must be a valid [Redis connection URI](https://redis-py.readthedocs.io/en/stable/connections.html#redis.Redis.from_url).
Set `REDIS_CLUSTER` to `True` to enable Redis Cluster mode. When enabled, the system will connect to Redis using cluster mode. This is useful when connecting to a Redis Cluster deployment.
## `RESUMABLE_STREAM_TTL_SECONDS`
Defaults to `False`.
Time-to-live in seconds for resumable stream data in Redis.
## `MOUNT_PREFIX`
When a run is created and the output is streamed, the stream can be configured to be resumable (e.g. `stream_resumable=True`). If a stream is resumable, output from the stream is temporarily stored in Redis. The TTL for this data can be configured by setting `RESUMABLE_STREAM_TTL_SECONDS`.
!!! info "Only Allowed in Self-Hosted Deployments"
The `MOUNT_PREFIX` environment variable is only allowed in Self-Hosted Deployment models, LangGraph Platform SaaS will not allow this environment variable.
See the [Python](https://langchain-ai.github.io/langgraph/cloud/reference/sdk/python_sdk_ref/#langgraph_sdk.client.RunsClient.stream) and [JS/TS](https://langchain-ai.github.io/langgraphjs/reference/classes/sdk_client.RunsClient.html#stream) SDKs for more details on how to implement resumable streams.
Set `MOUNT_PREFIX` to serve the LangGraph Server under a specific path prefix. This is useful for deployments where the server is behind a reverse proxy or load balancer that requires a specific path prefix.
Defaults to `120` seconds.
For example, if the server is to be served under `https://example.com/langgraph`, set `MOUNT_PREFIX` to `/langgraph`.
@@ -1,209 +0,0 @@
# LangGraph Server Changelog
[LangGraph Server](../../concepts/langgraph_server.md) is an API platform for creating and managing agent-based applications. It provides built-in persistence, a task queue, and supports deploying, configuring, and running assistants (agentic workflows) at scale. This changelog documents all notable updates, features, and fixes to LangGraph Server releases.
---
## v0.2.103 (2025-07-25)
- Corrected the metadata endpoint to ensure accurate data retrieval.
## v0.2.102 (2025-07-24)
- Captured interrupt events in the wait method to preserve legacy behavior and stream updates by default.
- Added support for SDK structlog in the JavaScript environment, enhancing logging capabilities.
## v0.2.101 (2025-07-24)
- Used the correct metadata endpoint for self-hosted environments, resolving an access issue.
## v0.2.99 (2025-07-22)
- Improved license validation by adding an in-memory cache and handling Redis connection errors more effectively.
- Automatically remove agents from memory that are removed from `langgraph.json` to prevent persistence issues.
- Ensured the UI namespace for generated UI is a valid JavaScript property name to prevent errors.
- Raised a 422 error for improved request validation feedback.
## v0.2.98 (2025-07-19)
- Added langgraph node context for improved log filtering and trace visibility.
## v0.2.97 (2025-07-19)
- Fixed scheduling issue with ckpt ingestion worker that occurred on isolated background loops.
- Ensured queue worker starts only after all migrations have completed.
- Added more detailed error messages for thread state issues and improved response handling when state updates fail.
- Exposed interrupt ID while retrieving thread state for enhanced API response details.
## v0.2.96 (2025-07-17)
- Added a fallback mechanism for configurable header patterns to handle exclude/include settings more effectively.
## v0.2.95 (2025-07-17)
- Avoided setting the future if it is already done to prevent redundant operations.
- Resolved compatibility errors in CI by switching from `typing.TypedDict` to `typing_extensions.TypedDict` for Python versions below 3.12.
## v0.2.94 (2025-07-16)
- Improved performance by omitting pending sends for langgraph versions 0.5 and above.
- Improved server startup logs to provide clearer warnings when the DD_API_KEY environment variable is set.
## v0.2.93 (2025-07-16)
- Removed the GIN index for run metadata to improve performance.
## v0.2.92 (2025-07-16)
- Enabled copying functionality for blobs and checkpoints, improving data management flexibility.
## v0.2.91 (2025-07-16)
- Reduced writes to the `checkpoint_blobs` table by inlining small values (null, numeric, str, etc.). This means we don't need to store extra values for channels that haven't been updated.
## v0.2.90 (2025-07-16)
- Improve checkpoint writes via node-local background queueing.
## v0.2.89 (2025-07-15)
- Decoupled checkpoint writing from thread/run state by removing foreign keys and updated logger to prevent timeout-related failures.
## v0.2.88 (2025-07-14)
- Removed the foreign key constraint for `thread` in the `run` table to simplify database schema.
## v0.2.87 (2025-07-14)
- Added more detailed logs for Redis worker signaling to improve debugging.
## v0.2.86 (2025-07-11)
- Honored tool descriptions in the `/mcp` endpoint to align with expected functionality.
## v0.2.85 (2025-07-10)
- Added support for the `on_disconnect` field to `runs/wait` and included disconnect logs for better debugging.
## v0.2.84 (2025-07-09)
- Removed unnecessary status updates to streamline thread handling and updated version to 0.2.84.
## v0.2.83 (2025-07-09)
- Reduced the default time-to-live for resumable streams to 2 minutes.
- Enhanced data submission logic to send data to both Beacon and LangSmith instance based on license configuration.
- Enabled submission of self-hosted data to a Langsmith instance when the endpoint is configured.
## v0.2.82 (2025-07-03)
- Addressed a race condition in background runs by implementing a lock using join, ensuring reliable execution across CTEs.
## v0.2.81 (2025-07-03)
- Optimized run streams by reducing initial wait time to improve responsiveness for older or non-existent runs.
## v0.2.80 (2025-07-03)
- Corrected parameter passing in the `logger.ainfo()` API call to resolve a TypeError.
## v0.2.79 (2025-07-02)
- Fixed a JsonDecodeError in checkpointing with remote graph by correcting JSON serialization to handle trailing slashes properly.
- Introduced a configuration flag to disable webhooks globally across all routes.
## v0.2.78 (2025-07-02)
- Added timeout retries to webhook calls to improve reliability.
- Added HTTP request metrics, including a request count and latency histogram, for enhanced monitoring capabilities.
## v0.2.77 (2025-07-02)
- Added HTTP metrics to improve performance monitoring.
- Changed the Redis cache delimiter to reduce conflicts with subgraph message names and updated caching behavior.
## v0.2.76 (2025-07-01)
- Updated Redis cache delimiter to prevent conflicts with subgraph messages.
## v0.2.74 (2025-06-30)
- Scheduled webhooks in an isolated loop to ensure thread-safe operations and prevent errors with PYTHONASYNCIODEBUG=1.
## v0.2.73 (2025-06-27)
- Fixed an infinite frame loop issue and removed the dict_parser due to structlog's unexpected behavior.
- Throw a 409 error on deadlock occurrence during run cancellations to handle lock conflicts gracefully.
## v0.2.72 (2025-06-27)
- Ensured compatibility with future langgraph versions.
- Implemented a 409 response status to handle deadlock issues during cancellation.
## v0.2.71 (2025-06-26)
- Improved logging for better clarity and detail regarding log types.
## v0.2.70 (2025-06-26)
- Improved error handling to better distinguish and log TimeoutErrors caused by users from internal run timeouts.
## v0.2.69 (2025-06-26)
- Added sorting and pagination to the crons API and updated schema definitions for improved accuracy.
## v0.2.66 (2025-06-26)
- Fixed a 404 error when creating multiple runs with the same thread_id using `on_not_exist="create"`.
## v0.2.65 (2025-06-25)
- Ensured that only fields from `assistant_versions` are returned when necessary.
- Ensured consistent data types for in-memory and PostgreSQL users, improving internal authentication handling.
## v0.2.64 (2025-06-24)
- Added descriptions to version entries for better clarity.
## v0.2.62 (2025-06-23)
- Improved user handling for custom authentication in the JS Studio.
- Added Prometheus-format run statistics to the metrics endpoint for better monitoring.
- Added run statistics in Prometheus format to the metrics endpoint.
## v0.2.61 (2025-06-20)
- Set a maximum idle time for Redis connections to prevent unnecessary open connections.
## v0.2.60 (2025-06-20)
- Enhanced error logging to include traceback details for dictionary operations.
- Added a `/metrics` endpoint to expose queue worker metrics for monitoring.
## v0.2.57 (2025-06-18)
- Removed CancelledError from retriable exceptions to allow local interrupts while maintaining retriability for workers.
- Introduced middleware to gracefully shut down the server after completing in-flight requests upon receiving a SIGINT.
- Reduced metadata stored in checkpoint to only include necessary information.
- Improved error handling in join runs to return error details when present.
## v0.2.56 (2025-06-17)
- Improved application stability by adding a handler for SIGTERM signals.
## v0.2.55 (2025-06-17)
- Improved the handling of cancellations in the queue entrypoint.
- Improved cancellation handling in the queue entry point.
## v0.2.54 (2025-06-16)
- Enhanced error message for LuaLock timeout during license validation.
- Fixed the $contains filter in custom auth by requiring an explicit ::text cast and updated tests accordingly.
- Ensured project and tenant IDs are formatted as UUIDs for consistency.
## v0.2.53 (2025-06-13)
- Resolved a timing issue to ensure the queue starts only after the graph is registered.
- Improved performance by setting thread and run status in a single query and enhanced error handling during checkpoint writes.
- Reduced the default background grace period to 3 minutes.
## v0.2.52 (2025-06-12)
- Now logging expected graphs when one is omitted to improve traceability.
- Implemented a time-to-live (TTL) feature for resumable streams.
- Improved query efficiency and consistency by adding a unique index and optimizing row locking.
## v0.2.51 (2025-06-12)
- Handled `CancelledError` by marking tasks as ready to retry, improving error management in worker processes.
- Added LG API version and request ID to metadata and logs for better tracking.
- Added LG API version and request ID to metadata and logs to improve traceability.
- Improved database performance by creating indexes concurrently.
- Ensured postgres write is committed only after the Redis running marker is set to prevent race conditions.
- Enhanced query efficiency and reliability by adding a unique index on thread_id/running, optimizing row locks, and ensuring deterministic run selection.
- Resolved a race condition by ensuring Postgres updates only occur after the Redis running marker is set.
## v0.2.46 (2025-06-07)
- Introduced a new connection for each operation while preserving transaction characteristics in Threads state `update()` and `bulk()` commands.
## v0.2.45 (2025-06-05)
- Enhanced streaming feature by incorporating tracing contexts.
- Removed an unnecessary query from the Crons.search function.
- Resolved connection reuse issue when scheduling next run for multiple cron jobs.
- Removed an unnecessary query in the Crons.search function to improve efficiency.
- Resolved an issue with scheduling the next cron run by improving connection reuse.
## v0.2.44 (2025-06-04)
- Enhanced the worker logic to exit the pipeline before continuing when the Redis message limit is reached.
- Introduced a ceiling for Redis message size with an option to skip messages larger than 128 MB for improved performance.
- Ensured the pipeline always closes properly to prevent resource leaks.
## v0.2.43 (2025-06-04)
- Improved performance by omitting logs in metadata calls and ensuring output schema compliance in value streaming.
- Ensured the connection is properly closed after use.
- Aligned output format to strictly adhere to the specified schema.
- Stopped sending internal logs in metadata requests to improve privacy.
## v0.2.42 (2025-06-04)
- Added timestamps to track the start and end of a request's run.
- Added tracer information to the configuration settings.
- Added support for streaming with tracing contexts.
## v0.2.41 (2025-06-03)
- Added locking mechanism to prevent errors in pipelined executions.
File diff suppressed because it is too large Load Diff
+8 -6
View File
@@ -58,10 +58,10 @@ Tools are useful whenever you want an agent to interact with external systems. E
### Memory
[Memory](../how-tos/memory/add-memory.md) is crucial for agents, enabling them to retain and utilize information across multiple steps of problem-solving. It operates on different scales:
[Memory](./memory.md) is crucial for agents, enabling them to retain and utilize information across multiple steps of problem-solving. It operates on different scales:
1. [Short-term memory](../how-tos/memory/add-memory.md#add-short-term-memory): Allows the agent to access information acquired during earlier steps in a sequence.
2. [Long-term memory](../how-tos/memory/add-memory.md#add-long-term-memory): Enables the agent to recall information from previous interactions, such as past messages in a conversation.
1. [Short-term memory](./memory.md#short-term-memory): Allows the agent to access information acquired during earlier steps in a sequence.
2. [Long-term memory](./memory.md#long-term-memory): Enables the agent to recall information from previous interactions, such as past messages in a conversation.
LangGraph provides full control over memory implementation:
@@ -69,7 +69,9 @@ LangGraph provides full control over memory implementation:
- [`Checkpointer`](./persistence.md#checkpoints): Mechanism to store state at every step across different interactions within a session.
- [`Store`](./persistence.md#memory-store): Mechanism to store user-specific or application-level data across sessions.
This flexible approach allows you to tailor the memory system to your specific agent architecture needs. Effective memory management enhances an agent's ability to maintain context, learn from past experiences, and make more informed decisions over time. For a practical guide on adding and managing memory, see [Memory](../how-tos/memory/add-memory.md).
This flexible approach allows you to tailor the memory system to your specific agent architecture needs. For a practical guide on adding memory to your graph, see [this tutorial](../how-tos/persistence.ipynb).
Effective [memory management](../how-tos/memory.ipynb) enhances an agent's ability to maintain context, learn from past experiences, and make more informed decisions over time.
### Planning
@@ -97,7 +99,7 @@ Parallel processing is vital for efficient multi-agent systems and complex tasks
- Implementation of map-reduce-like operations
- Efficient handling of independent subtasks
For practical implementation, see our [map-reduce tutorial](../how-tos/graph-api.md#map-reduce-and-the-send-api)
For practical implementation, see our [map-reduce tutorial](../how-tos/graph-api.ipynb#map-reduce-and-the-send-api)
### Subgraphs
@@ -107,7 +109,7 @@ For practical implementation, see our [map-reduce tutorial](../how-tos/graph-api
- Hierarchical organization of agent teams
- Controlled communication between agents and the main system
Subgraphs communicate with the parent graph through overlapping keys in the state schema. This enables flexible, modular agent design. For implementation details, refer to our [subgraph how-to guide](../how-tos/subgraph.md).
Subgraphs communicate with the parent graph through overlapping keys in the state schema. This enables flexible, modular agent design. For implementation details, refer to our [subgraph how-to guide](../how-tos/subgraph.ipynb).
### Reflection
+2 -2
View File
@@ -48,7 +48,7 @@ Below are examples of directory structures for Python and JavaScript application
│ ├── utils # utilities for your graph
│ │ ├── __init__.py
│ │ ├── tools.py # tools for your graph
│ │ ├── nodes.py # node functions for your graph
│ │ ├── nodes.py # node functions for you graph
│ │ └── state.py # state definition of your graph
│ ├── __init__.py
│ └── agent.py # code for constructing your graph
@@ -64,7 +64,7 @@ Below are examples of directory structures for Python and JavaScript application
├── src # all project code lies within here
│ ├── utils # optional utilities for your graph
│ │ ├── tools.ts # tools for your graph
│ │ ├── nodes.ts # node functions for your graph
│ │ ├── nodes.ts # node functions for you graph
│ │ └── state.ts # state definition of your graph
│ └── agent.ts # code for constructing your graph
├── package.json # package dependencies
+5 -5
View File
@@ -1,6 +1,6 @@
# Assistants
**Assistants** allow you to manage configurations (like prompts, LLM selection, tools) separately from your graph's core logic, enabling rapid changes that don't alter the graph architecture. It is a way to create multiple specialized versions of the same graph architecture, each optimized for different use cases through context/configuration variations rather than structural changes.
**Assistants** allow you to manage configurations (like prompts, LLM selection, tools) separately from your graph's core logic, enabling rapid changes that don't alter the graph architecture. It is a way to create multiple specialized versions of the same graph architecture, each optimized for different use cases through configuration variations rather than structural changes.
For example, imagine a general-purpose writing agent built on a common graph architecture. While the structure remains the same, different writing styles—such as blog posts and tweets—require tailored configurations to optimize performance. To support these variations, you can create multiple assistants (e.g., one for blogs and another for tweets) that share the underlying graph but differ in model selection and system prompt.
@@ -14,8 +14,8 @@ The LangGraph Cloud API provides several endpoints for creating and managing ass
## Configuration
Assistants build on the LangGraph open source concepts of configuration and [runtime context](low_level.md#runtime-context).
While these features are available in the open source LangGraph library, assistants are only present in [LangGraph Platform](langgraph_platform.md). This is due to the fact that assistants are tightly coupled to your deployed graph. Upon deployment, LangGraph Server will automatically create a default assistant for each graph using the graph's default context and configuration settings.
Assistants build on the LangGraph open source concept of [configuration](low_level.md#configuration).
While configuration is available in the open source LangGraph library, assistants are only present in [LangGraph Platform](langgraph_platform.md). This is due to the fact that assistants are tightly coupled to your deployed graph. Upon deployment, LangGraph Server will automatically create a default assistant for each graph using the graph's default configuration settings.
In practice, an assistant is just an _instance_ of a graph with a specific configuration. Therefore, multiple assistants can reference the same graph but can contain different configurations (e.g. prompts, models, tools). The LangGraph Server API provides several endpoints for creating and managing assistants. See the [API reference](../cloud/reference/api/api_ref.html) and [this how-to](../cloud/how-tos/configuration_cloud.md) for more details on how to create assistants.
@@ -26,6 +26,6 @@ Once you've created an assistant, subsequent edits to that assistant will create
## Execution
A **run** is an invocation of an assistant. Each run may have its own input, configuration, context, and metadata, which may affect execution and output of the underlying graph. A run can optionally be executed on a [thread](./persistence.md#threads).
A **run** is an invocation of an assistant. Each run may have its own input, configuration, and metadata, which may affect execution and output of the underlying graph. A run can optionally be executed on a [thread](../../concepts/persistence.md#threads).
The LangGraph Platform API provides several endpoints for creating and managing runs. See the [API reference](../cloud/reference/api/api_ref.html#tag/thread-runs/) for more details.
The LangGraph Platform API provides several endpoints for creating and managing runs. See the [API reference](../../cloud/reference/api/api_ref.html#tag/thread-runs/) for more details.
-48
View File
@@ -143,54 +143,6 @@ The returned user information is available:
In many of our tutorials, we will just show the "authorization" parameter to be concise, but you can opt to accept more information as needed
to implement your custom authentication scheme.
### Agent authentication
Custom authentication permits delegated access. The values you return in `@auth.authenticate` are added to the run context, giving agents user-scoped credentials lets them access resources on the users behalf.
```mermaid
sequenceDiagram
%% Actors
participant ClientApp as Client
participant AuthProv as Auth Provider
participant LangGraph as LangGraph Backend
participant SecretStore as Secret Store
participant ExternalService as External Service
%% Platform login / AuthN
ClientApp ->> AuthProv: 1. Login (username / password)
AuthProv -->> ClientApp: 2. Return token
ClientApp ->> LangGraph: 3. Request with token
Note over LangGraph: 4. Validate token (@auth.authenticate)
LangGraph -->> AuthProv: 5. Fetch user info
AuthProv -->> LangGraph: 6. Confirm validity
%% Fetch user tokens from secret store
LangGraph ->> SecretStore: 6a. Fetch user tokens
SecretStore -->> LangGraph: 6b. Return tokens
Note over LangGraph: 7. Apply access control (@auth.on.*)
%% External Service round-trip
LangGraph ->> ExternalService: 8. Call external service (with header)
Note over ExternalService: 9. External service validates header and executes action
ExternalService -->> LangGraph: 10. Service response
%% Return to caller
LangGraph -->> ClientApp: 11. Return resources
```
After authentication, the platform creates a special configuration object that is passed to your graph and all nodes via the configurable context.
This object contains information about the current user, including any custom fields you return from your [`@auth.authenticate`](../cloud/reference/sdk/python_sdk_ref.md#langgraph_sdk.auth.Auth.authenticate) handler.
To enable an agent to act on behalf of the user, use [custom authentication middleware](../how-tos/auth/custom_auth.md). This will allow the agent to interact with external systems like MCP servers, external databases, and even other agents on behalf of the user.
For more information, see the [Use custom auth](../how-tos/auth/custom_auth.md#enable-agent-authentication) guide.
### Agent authentication with MCP
For information on how to authenticate an agent to an MCP server, see the [MCP conceptual guide](../concepts/mcp.md).
## Authorization
After authentication, LangGraph calls your [`@auth.on`](../cloud/reference/sdk/python_sdk_ref.md#langgraph_sdk.auth.Auth.on) handlers to control access to specific resources (e.g., threads, assistants, crons). These handlers can:
+14
View File
@@ -0,0 +1,14 @@
---
search:
boost: 2
---
# Breakpoints
Breakpoints pause graph execution at defined points and let you step through each stage. They use LangGraph's [**persistence layer**](./persistence.md), which saves the graph state after each step.
With breakpoints, you can inspect the graph's state and node inputs at any point. Execution pauses **indefinitely** until you resume, as the checkpointer preserves the state.
<figure markdown="1">
![image](img/breakpoints.png){: style="max-height:400px"}
<figcaption>An example graph consisting of 3 sequential steps with a breakpoint before step_3. </figcaption> </figure>
+5 -5
View File
@@ -10,7 +10,7 @@ search:
There are two free options for deploying LangGraph applications via the LangGraph Server:
1. [Local](../tutorials/langgraph-platform/local-server.md): Deploy for local testing and development.
1. [Standalone Container (Lite)](../concepts/langgraph_standalone_container.md): A limited version of Standalone Container for deployments unlikely to see more than 1 million node executions per year and that do not need crons and other enterprise features. Standalone Container (Lite) deployment option is free with a LangSmith API key.
1. [Standalone Container (Lite)](../concepts/langgraph_standalone_container.md): A limited version of Standalone Container for deployments unlikely to see more that 1 million node executions per year and that do not need crons and other enterprise features. Standalone Container (Lite) deployment option is free with a LangSmith API key.
## Production deployment
@@ -18,9 +18,9 @@ There are 4 main options for deploying with the [LangGraph Platform](langgraph_p
1. [Cloud SaaS](#cloud-saas)
1. [Self-Hosted Data Plane](#self-hosted-data-plane)
1. [Self-Hosted Data Plane<sup>(Beta)</sup>](#self-hosted-data-plane)
1. [Self-Hosted Control Plane](#self-hosted-control-plane)
1. [Self-Hosted Control Plane<sup>(Beta)</sup>](#self-hosted-control-plane)
1. [Standalone Container](#standalone-container)
@@ -50,7 +50,7 @@ For more information, please see:
## Self-Hosted Data Plane
!!! info "Important"
The Self-Hosted Data Plane deployment option requires an [Enterprise](../concepts/plans.md) plan.
The Self-Hosted Data Plane deployment option is currently in beta stage and requires an [Enterprise](../concepts/plans.md) plan.
The [Self-Hosted Data Plane](./langgraph_self_hosted_data_plane.md) deployment option is a "hybrid" model for deployment where we manage the [control plane](./langgraph_control_plane.md) in our cloud and you manage the [data plane](./langgraph_data_plane.md) in your cloud. This option provides a way to securely manage your data plane infrastructure, while offloading control plane management to us.
@@ -66,7 +66,7 @@ For more information, please see:
## Self-Hosted Control Plane
!!! info "Important"
The Self-Hosted Control Plane deployment option requires an [Enterprise](../concepts/plans.md) plan.
The Self-Hosted Control Plane deployment option is currently in beta stage and requires an [Enterprise](../concepts/plans.md) plan.
The [Self-Hosted Control Plane](./langgraph_self_hosted_control_plane.md) deployment option is a fully self-hosted model for deployment where you manage the [control plane](./langgraph_control_plane.md) and [data plane](./langgraph_data_plane.md) in your cloud. This option gives you full control and responsibility of the control plane and data plane infrastructure.
+4 -4
View File
@@ -48,7 +48,7 @@ If a [node](./low_level.md#nodes) contains multiple operations, you may find it
from typing_extensions import TypedDict
import uuid
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.checkpoint.memory import MemorySaver
from langgraph.graph import StateGraph, START, END
import requests
@@ -74,7 +74,7 @@ If a [node](./low_level.md#nodes) contains multiple operations, you may find it
builder.add_edge("call_api", END)
# Specify a checkpointer
checkpointer = InMemorySaver()
checkpointer = MemorySaver()
# Compile the graph with the checkpointer
graph = builder.compile(checkpointer=checkpointer)
@@ -94,7 +94,7 @@ If a [node](./low_level.md#nodes) contains multiple operations, you may find it
from typing_extensions import TypedDict
import uuid
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.checkpoint.memory import MemorySaver
from langgraph.func import task
from langgraph.graph import StateGraph, START, END
import requests
@@ -129,7 +129,7 @@ If a [node](./low_level.md#nodes) contains multiple operations, you may find it
builder.add_edge("call_api", END)
# Specify a checkpointer
checkpointer = InMemorySaver()
checkpointer = MemorySaver()
# Compile the graph with the checkpointer
graph = builder.compile(checkpointer=checkpointer)
+2 -6
View File
@@ -47,7 +47,7 @@ LangGraph is a stateful, orchestration framework that brings added control to ag
No. LangGraph Platform is proprietary software.
There is a free, self-hosted version of LangGraph Platform with access to basic features. The Cloud SaaS deployment option and the Self-Hosted deployment options are paid services. [Contact our sales team](https://www.langchain.com/contact-sales) to learn more.
There is a free, self-hosted version of LangGraph Platform with access to basic features. The Cloud SaaS deployment option is free while in beta, but will eventually be a paid service. We will always give ample notice before charging for a service and reward our early adopters with preferential pricing. The Self-Hosted deployment options are paid services. [Contact our sales team](https://www.langchain.com/contact-sales) to learn more.
For more information, see our [LangGraph Platform pricing page](https://www.langchain.com/pricing-langgraph-platform).
@@ -63,8 +63,4 @@ Yes! LangGraph is totally ambivalent to what LLMs are used under the hood. The m
Yes! You can use the [development version of LangGraph Server](../tutorials/langgraph-platform/local-server.md) to run the backend locally.
This will connect to the studio frontend hosted as part of LangSmith.
If you set an environment variable of `LANGSMITH_TRACING=false`, then no traces will be sent to LangSmith.
## What does "nodes executed" mean for LangGraph Platform usage?
**Nodes Executed** is the aggregate number of nodes in a LangGraph application that are called and completed successfully during an invocation of the application. If a node in the graph is not called during execution or ends in an error state, these nodes will not be counted. If a node is called and completes successfully multiple times, each occurrence will be counted.
If you set an environment variable of `LANGSMITH_TRACING=false`, then no traces will be sent to LangSmith.
+43 -48
View File
@@ -7,7 +7,7 @@ search:
## Overview
The **Functional API** allows you to add LangGraph's key features — [persistence](./persistence.md), [memory](../how-tos/memory/add-memory.md), [human-in-the-loop](./human_in_the_loop.md), and [streaming](./streaming.md) — to your applications with minimal changes to your existing code.
The **Functional API** allows you to add LangGraph's key features — [persistence](./persistence.md), [memory](./memory.md), [human-in-the-loop](./human_in_the_loop.md), and [streaming](./streaming.md) — to your applications with minimal changes to your existing code.
It is designed to integrate these features into existing code that may use standard language primitives for branching and control flow, such as `if` statements, `for` loops, and function calls. Unlike many data orchestration frameworks that require restructuring code into an explicit pipeline or DAG, the Functional API allows you to incorporate these capabilities without enforcing a rigid execution model.
@@ -18,28 +18,17 @@ The Functional API uses two key building blocks:
This provides a minimal abstraction for building workflows with state management and streaming.
!!! tip
For information on how to use the functional API, see [Use Functional API](../how-tos/use-functional-api.md).
## Functional API vs. Graph API
For users who prefer a more declarative approach, LangGraph's [Graph API](./low_level.md) allows you to define workflows using a Graph paradigm. Both APIs share the same underlying runtime, so you can use them together in the same application.
Here are some key differences:
- **Control flow**: The Functional API does not require thinking about graph structure. You can use standard Python constructs to define workflows. This will usually trim the amount of code you need to write.
- **Short-term memory**: The **GraphAPI** requires declaring a [**State**](./low_level.md#state) and may require defining [**reducers**](./low_level.md#reducers) to manage updates to the graph state. `@entrypoint` and `@tasks` do not require explicit state management as their state is scoped to the function and is not shared across functions.
- **Checkpointing**: Both APIs generate and use checkpoints. In the **Graph API** a new checkpoint is generated after every [superstep](./low_level.md). In the **Functional API**, when tasks are executed, their results are saved to an existing checkpoint associated with the given entrypoint instead of creating a new checkpoint.
- **Visualization**: The Graph API makes it easy to visualize the workflow as a graph which can be useful for debugging, understanding the workflow, and sharing with others. The Functional API does not support visualization as the graph is dynamically generated during runtime.
!!! tip
For users who prefer a more declarative approach, LangGraph's [Graph API](./low_level.md) allows you to define workflows using a Graph paradigm. Both APIs share the same underlying runtime, so you can use them together in the same application.
Please see the [Functional API vs. Graph API](#functional-api-vs-graph-api) section for a comparison of the two paradigms.
## Example
Below we demonstrate a simple application that writes an essay and [interrupts](human_in_the_loop.md) to request human review.
```python
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.checkpoint.memory import MemorySaver
from langgraph.func import entrypoint, task
from langgraph.types import interrupt
@@ -50,7 +39,7 @@ def write_essay(topic: str) -> str:
time.sleep(1) # A placeholder for a long-running task.
return f"An essay about topic: {topic}"
@entrypoint(checkpointer=InMemorySaver())
@entrypoint(checkpointer=MemorySaver())
def workflow(topic: str) -> dict:
"""A simple workflow that writes an essay and asks for a review."""
essay = write_essay("cat").result()
@@ -79,54 +68,51 @@ def workflow(topic: str) -> dict:
```python
import time
import uuid
from langgraph.func import entrypoint, task
from langgraph.types import interrupt
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.checkpoint.memory import MemorySaver
@task
def write_essay(topic: str) -> str:
"""Write an essay about the given topic."""
time.sleep(1) # This is a placeholder for a long-running task.
time.sleep(1) # This is a placeholder for a long-running task.
return f"An essay about topic: {topic}"
@entrypoint(checkpointer=InMemorySaver())
@entrypoint(checkpointer=MemorySaver())
def workflow(topic: str) -> dict:
"""A simple workflow that writes an essay and asks for a review."""
essay = write_essay("cat").result()
is_approved = interrupt(
{
# Any json-serializable payload provided to interrupt as argument.
# It will be surfaced on the client side as an Interrupt when streaming data
# from the workflow.
"essay": essay, # The essay we want reviewed.
# We can add any additional information that we need.
# For example, introduce a key called "action" with some instructions.
"action": "Please approve/reject the essay",
}
)
is_approved = interrupt({
# Any json-serializable payload provided to interrupt as argument.
# It will be surfaced on the client side as an Interrupt when streaming data
# from the workflow.
"essay": essay, # The essay we want reviewed.
# We can add any additional information that we need.
# For example, introduce a key called "action" with some instructions.
"action": "Please approve/reject the essay",
})
return {
"essay": essay, # The essay that was generated
"is_approved": is_approved, # Response from HIL
"essay": essay, # The essay that was generated
"is_approved": is_approved, # Response from HIL
}
thread_id = str(uuid.uuid4())
config = {"configurable": {"thread_id": thread_id}}
config = {
"configurable": {
"thread_id": thread_id
}
}
for item in workflow.stream("cat", config):
print(item)
# > {'write_essay': 'An essay about topic: cat'}
# > {
# > '__interrupt__': (
# > Interrupt(
# > value={
# > 'essay': 'An essay about topic: cat',
# > 'action': 'Please approve/reject the essay'
# > },
# > id='b9b2b9d788f482663ced6dc755c9e981'
# > ),
# > )
# > }
```
```pycon
{'write_essay': 'An essay about topic: cat'}
{'__interrupt__': (Interrupt(value={'essay': 'An essay about topic: cat', 'action': 'Please approve/reject the essay'}, resumable=True, ns=['workflow:f7b8508b-21c0-8b4c-5958-4e8de74d2684'], when='during'),)}
```
An essay has been written and is ready for review. Once the review is provided, we can resume the workflow:
@@ -546,6 +532,15 @@ While different runs of a workflow can produce different results, resuming a **s
Idempotency ensures that running the same operation multiple times produces the same result. This helps prevent duplicate API calls and redundant processing if a step is rerun due to a failure. Always place API calls inside **tasks** functions for checkpointing, and design them to be idempotent in case of re-execution. Re-execution can occur if a **task** starts, but does not complete successfully. Then, if the workflow is resumed, the **task** will run again. Use idempotency keys or verify existing results to avoid duplication.
## Functional API vs. Graph API
The **Functional API** and the [Graph APIs (StateGraph)](./low_level.md#stategraph) provide two different paradigms to create applications with LangGraph. Here are some key differences:
- **Control flow**: The Functional API does not require thinking about graph structure. You can use standard Python constructs to define workflows. This will usually trim the amount of code you need to write.
- **Short-term memory**: The **GraphAPI** requires declaring a [**State**](./low_level.md#state) and may require defining [**reducers**](./low_level.md#reducers) to manage updates to the graph state. `@entrypoint` and `@tasks` do not require explicit state management as their state is scoped to the function and is not shared across functions.
- **Checkpointing**: Both APIs generate and use checkpoints. In the **Graph API** a new checkpoint is generated after every [superstep](./low_level.md). In the **Functional API**, when tasks are executed, their results are saved to an existing checkpoint associated with the given entrypoint instead of creating a new checkpoint.
- **Visualization**: The Graph API makes it easy to visualize the workflow as a graph which can be useful for debugging, understanding the workflow, and sharing with others. The Functional API does not support visualization as the graph is dynamically generated during runtime.
## Common Pitfalls
### Handling side effects
+10 -25
View File
@@ -11,36 +11,21 @@ hide:
# Human-in-the-loop
To review, edit, and approve tool calls in an agent or workflow, [use LangGraph's human-in-the-loop features](../how-tos/human_in_the_loop/add-human-in-the-loop.md) to enable human intervention at any point in a workflow. This is especially useful in large language model (LLM)-driven applications where model output may require validation, correction, or additional context.
<figure markdown="1">
![image](../concepts/img/human_in_the_loop/tool-call-review.png){: style="max-height:400px"}
</figure>
!!! tip
For information on how to use human-in-the-loop, see [Enable human intervention](../how-tos/human_in_the_loop/add-human-in-the-loop.md) and [Human-in-the-loop using Server API](../cloud/how-tos/add-human-in-the-loop.md).
LangGraph supports robust **human-in-the-loop (HIL)** workflows, enabling human intervention at any point in an automated process. This is especially useful in large language model (LLM)-driven applications where model output may require validation, correction, or additional context.
## Key capabilities
* **Persistent execution state**: Interrupts use LangGraph's [persistence](./persistence.md) layer, which saves the graph state, to indefinitely pause graph execution until you resume. This is possible because LangGraph checkpoints the graph state after each step, which allows the system to persist execution context and later resume the workflow, continuing from where it left off. This supports asynchronous human review or input without time constraints.
* **Persistent execution state**: LangGraph checkpoints the graph state after each step, allowing execution to pause indefinitely at defined nodes. This supports asynchronous human review or input without time constraints.
There are two ways to pause a graph:
* **Flexible integration points**: HIL logic can be introduced at any point in the workflow. This allows targeted human involvement, such as approving API calls, correcting outputs, or guiding conversations.
- [Dynamic interrupts](../how-tos/human_in_the_loop/add-human-in-the-loop.md#pause-using-interrupt): Use `interrupt` to pause a graph from inside a specific node, based on the current state of the graph.
- [Static interrupts](../how-tos/human_in_the_loop/add-human-in-the-loop.md#debug-with-interrupts): Use `interrupt_before` and `interrupt_after` to pause the graph at defined points, either before or after a node executes.
## Typical use cases
<figure markdown="1">
![image](./img/breakpoints.png){: style="max-height:400px"}
<figcaption>An example graph consisting of 3 sequential steps with a breakpoint before step_3. </figcaption> </figure>
1. [**🛠️ Reviewing tool calls**](../how-tos/human_in_the_loop/add-human-in-the-loop.md#review-tool-calls): Humans can review, edit, or approve tool calls requested by the LLM before tool execution.
2. **✅ Validating LLM outputs**: Humans can review, edit, or approve content generated by the LLM.
3. **💡 Providing context**: Enable the LLM to explicitly request human input for clarification or additional details or to support multi-turn conversations.
* **Flexible integration points**: Human-in-the-loop logic can be introduced at any point in the workflow. This allows targeted human involvement, such as approving API calls, correcting outputs, or guiding conversations.
## Implementation
## Patterns
There are four typical design patterns that you can implement using `interrupt` and `Command`:
- [Approve or reject](../how-tos/human_in_the_loop/add-human-in-the-loop.md#approve-or-reject): Pause the graph before a critical step, such as an API call, to review and approve the action. If the action is rejected, you can prevent the graph from executing the step, and potentially take an alternative action. This pattern often involves routing the graph based on the human's input.
- [Edit graph state](../how-tos/human_in_the_loop/add-human-in-the-loop.md#review-and-edit-state): Pause the graph to review and edit the graph state. This is useful for correcting mistakes or updating the state with additional information. This pattern often involves updating the state with the human's input.
- [Review tool calls](../how-tos/human_in_the_loop/add-human-in-the-loop.md#review-tool-calls): Pause the graph to review and edit tool calls requested by the LLM before tool execution.
- [Validate human input](../how-tos/human_in_the_loop/add-human-in-the-loop.md#validate-human-input): Pause the graph to validate human input before proceeding with the next step.
* `interrupt` function: Pauses execution at a specific point, presents information for human review.
* `Command` primitive: Used to resume execution with a value provided by the human.
Binary file not shown.

Before

Width:  |  Height:  |  Size: 121 KiB

+1 -6
View File
@@ -9,18 +9,13 @@ search:
## Installation
The LangGraph CLI can be installed via pip or [Homebrew](https://brew.sh/):
The LangGraph CLI can be installed via pip:
=== "pip"
```bash
pip install langgraph-cli
```
=== "Homebrew"
```bash
brew install langgraph-cli
```
## Commands
LangGraph CLI provides the following core functionality:
+16 -40
View File
@@ -19,14 +19,14 @@ From the control plane UI, you can:
- Update a deployment.
- Update environment variables for a deployment.
- View build and server logs of a deployment.
- View deployment metrics such as CPU and memory usage.
- View deployment metrics like CPU and memory usage.
- Delete a deployment.
The Control Plane UI is embedded in [LangSmith](https://docs.smith.langchain.com/langgraph_cloud).
## Control Plane API
This section describes the data model of the control plane API. The API is used to create, update, and delete deployments. See the [control plane API reference](../cloud/reference/api/api_ref_control_plane.md) for more details.
This section describes data model of the control plane API. The API is used to create, update, and delete deployments. However, they are not publicly accessible.
### Deployment
@@ -34,7 +34,11 @@ A deployment is an instance of a LangGraph Server. A single deployment can have
### Revision
A revision is an iteration of a deployment. When a new deployment is created, an initial revision is automatically created. To deploy code changes or update secrets for a deployment, a new revision must be created.
A revision is an iteration of a deployment. When a new deployment is created, an initial revision is automatically created. To deploy code changes or update environment variables for a deployment, a new revision must be created.
### Environment Variable
Environment variables are set for a deployment. All environment variables are stored as secrets (i.e. saved in a secrets store).
## Control Plane Features
@@ -46,40 +50,21 @@ For simplicity, the control plane offers two deployment types with different res
| **Deployment Type** | **CPU/Memory** | **Scaling** | **Database** |
|---------------------|-----------------|---------------------|----------------------------------------------------------------------------------|
| Development | 1 CPU, 1 GB RAM | Up to 1 replica | 10 GB disk, no backups |
| Production | 2 CPU, 2 GB RAM | Up to 10 replicas | Autoscaling disk, automatic backups, highly available (multi-zone configuration) |
| Development | 1 CPU, 1 GB RAM | Up to 1 container | 10 GB disk, no backups |
| Production | 2 CPU, 2 GB RAM | Up to 10 containers | Autoscaling disk, automatic backups, highly available (multi-zone configuration) |
CPU and memory resources are per replica.
CPU and memory resources are per container.
!!! warning "Immutable Deployment Type"
Once a deployment is created, the deployment type cannot be changed.
!!! info "Self-Hosted Deployment"
Resources for [Self-Hosted Data Plane](../concepts/langgraph_self_hosted_data_plane.md) and [Self-Hosted Control Plane](../concepts/langgraph_self_hosted_control_plane.md) deployments can be fully customized. Deployment types are only applicable for [Cloud SaaS](../concepts/langgraph_cloud.md) deployments.
!!! info "Resource Customization"
For `Production` type deployments, resources can be manually increased on a case-by-case basis depending on use case and capacity constraints. Contact support@langchain.dev to request an increase in resources.
#### Production
For `Development` types deployments, database disk size can be manually increased on a case-by-case basis depending on use case and capacity constraints. For most use cases, [TTLs](../how-tos/ttl/configure_ttl.md) should be configured to manage disk usage. Contact support@langchain.dev to request an increase in resources.
`Production` type deployments are suitable for "production" workloads. For example, select `Production` for customer-facing applications in the critical path.
Resources for `Production` type deployments can be manually increased on a case-by-case basis depending on use case and capacity constraints. Contact support@langchain.dev to request an increase in resources.
#### Development
`Development` type deployments are suitable development and testing. For example, select `Development` for internal testing environments. `Development` type deployments are not suitable for "production" workloads.
!!! danger "Preemptible Compute Infrastructure"
`Development` type deployments (API server, queue server, and database) are provisioned on preemptible compute infrastructure. This means the compute infrastructure **may be terminated at any time without notice**. This may result in intermittent...
- Redis connection timeouts/errors
- Postgres connection timeouts/errors
- Failed or retrying background runs
This behavior is expected. Preemptible compute infrastructure **significantly reduces the cost to provision a `Development` type deployment**. By design, LangGraph Server is fault-tolerant. The implementation will automatically attempt to recover from Redis/Postgres connection errors and retry failed background runs.
`Production` type deployments are provisioned on durable compute infrastructure, not preemptible compute infrastructure.
Database disk size for `Development` type deployments can be manually increased on a case-by-case basis depending on use case and capacity constraints. For most use cases, [TTLs](../how-tos/ttl/configure_ttl.md) should be configured to manage disk usage. Contact support@langchain.dev to request an increase in resources.
Resources for [Self-Hosted Data Plane](../concepts/langgraph_self_hosted_data_plane.md) and [Self-Hosted Control Plane](../concepts/langgraph_self_hosted_control_plane.md) deployments can be fully customized.
### Database Provisioning
@@ -110,20 +95,11 @@ After a deployment is ready, the control plane monitors the deployment and recor
- CPU and memory usage of the deployment.
- Number of container restarts.
- Number of replicas (this will increase with [autoscaling](../concepts/langgraph_data_plane.md#autoscaling)).
- [Postgres](../concepts/langgraph_data_plane.md#postgres) CPU, memory usage, and disk usage.
- [LangGraph Server queue](../concepts/langgraph_server.md#persistence-and-task-queue) pending/active run count.
- [LangGraph Server API](../concepts/langgraph_server.md) success response count, error response count, and latency.
These metrics are displayed as charts in the Control Plane UI.
### LangSmith Integration
A [LangSmith](https://docs.smith.langchain.com/) tracing project and LangSmith API key are automatically created for each deployment. The deployment uses the API key to automatically send traces to LangSmith.
A [LangSmith](https://docs.smith.langchain.com/) tracing project is automatically created for each deployment. The tracing project has the same name as the deployment. When creating a deployment, the `LANGCHAIN_TRACING` and `LANGSMITH_API_KEY`/`LANGCHAIN_API_KEY` environment variables do not need to be specified; they are set automatically by the control plane.
- The tracing project has the same name as the deployment.
- The API key has the description `LangGraph Platform: <deployment_name>`.
- The API key is never revealed and cannot be deleted manually.
- When creating a deployment, the `LANGCHAIN_TRACING` and `LANGSMITH_API_KEY`/`LANGCHAIN_API_KEY` environment variables do not need to be specified; they are set automatically by the control plane.
When a deployment is deleted, the traces and the tracing project are not deleted. However, the API will be deleted when the deployment is deleted.
When a deployment is deleted, the traces and the tracing project are not deleted.
+1 -10
View File
@@ -50,22 +50,13 @@ Runs in a LangGraph Server may be retried for specific failures (currently only
This section describes various features of the data plane.
### Data Region
!!! info "Only for Cloud SaaS"
Data regions are only applicable for [Cloud SaaS](../concepts/langgraph_cloud.md) deployments.
Deployments can be created in 2 data regions: US and EU
The data region for a deployment is implied by the data region of the LangSmith organization where the deployment is created. Deployments and the underlying database for the deployments cannot be migrated between data regions.
### Autoscaling
[`Production` type](../concepts/langgraph_control_plane.md#deployment-types) deployments automatically scale up to 10 containers. Scaling is based on 3 metrics:
1. CPU utilization
1. Memory utilization
1. Number of pending (in progress) [runs](./assistants.md#execution)
1. Number of pending (in progress) [runs](../cloud/concepts/runs.md)
For CPU utilization, the autoscaler targets 75% utilization. This means the autoscaler will scale the number of containers up or down to ensure that CPU utilization is at or near 75%. For memory utilization, the autoscaler targets 75% utilization as well.
@@ -3,7 +3,7 @@
There are two versions of the self-hosted deployment: [Self-Hosted Data Plane](./deployment_options.md#self-hosted-data-plane) and [Self-Hosted Control Plane](./deployment_options.md#self-hosted-control-plane).
!!! info "Important"
The Self-Hosted Control Plane deployment option requires an [Enterprise](plans.md) plan.
The Self-Hosted Control Plane deployment option is currently in beta stage and requires an [Enterprise](plans.md) plan.
## Requirements
@@ -8,7 +8,7 @@ search:
There are two versions of the self-hosted deployment: [Self-Hosted Data Plane](./deployment_options.md#self-hosted-data-plane) and [Self-Hosted Control Plane](./deployment_options.md#self-hosted-control-plane).
!!! info "Important"
The Self-Hosted Data Plane deployment option requires an [Enterprise](plans.md) plan.
The Self-Hosted Data Plane deployment option is currently in beta stage and requires an [Enterprise](plans.md) plan.
## Requirements
+2 -2
View File
@@ -7,7 +7,7 @@ search:
**LangGraph Server** offers an API for creating and managing agent-based applications. It is built on the concept of [assistants](assistants.md), which are agents configured for specific tasks, and includes built-in [persistence](persistence.md#memory-store) and a **task queue**. This versatile API supports a wide range of agentic application use cases, from background processing to real-time interactions.
Use LangGraph Server to create and manage [assistants](assistants.md), [threads](./persistence.md#threads), [runs](./assistants.md#execution), [cron jobs](../cloud/concepts/cron_jobs.md), [webhooks](../cloud/concepts/webhooks.md), and more.
Use LangGraph Server to create and manage [assistants](assistants.md), [threads](./persistence.md#threads), [runs](../cloud/concepts/runs.md), [cron jobs](../cloud/concepts/cron_jobs.md), [webhooks](../cloud/concepts/webhooks.md), and more.
!!! tip "API reference"
@@ -17,7 +17,7 @@ Use LangGraph Server to create and manage [assistants](assistants.md), [threads]
There are two versions of LangGraph Server:
- `Lite` is a limited version of the LangGraph Server that you can run locally or in a self-hosted manner (up to 1 million [nodes executed](../concepts/faq.md#what-does-nodes-executed-mean-for-langgraph-platform-usage) per year).
- `Lite` is a limited version of the LangGraph Server that you can run locally or in a self-hosted manner (up to 1 million nodes executed per year).
- `Enterprise` is the full version of the LangGraph Server. To use the `Enterprise` version, you must acquire a license key that you will need to specify when running the Docker image. To acquire a license key, please email sales@langchain.dev.
Feature Differences:
@@ -17,10 +17,6 @@ The Standalone Container deployment option is the least restrictive model for de
| **Where is it hosted?** | n/a | Your cloud |
| **Who provisions and manages it?** | n/a | You |
!!! warning
LangGraph Platform should not be deployed in serverless environments. Scale to zero may cause task loss and scaling up will not work reliably.
## Architecture
![Standalone Container](./img/langgraph_platform_deployment_architecture.png)
+38 -50
View File
@@ -45,9 +45,9 @@ The first thing you do when you define a graph is define the `State` of the grap
### Schema
The main documented way to specify the schema of a graph is by using a [`TypedDict`](https://docs.python.org/3/library/typing.html#typing.TypedDict). If you want to provide default values in your state, use a [`dataclass`](https://docs.python.org/3/library/dataclasses.html). We also support using a Pydantic [BaseModel](../how-tos/graph-api.md#use-pydantic-models-for-graph-state) as your graph state if you want recursive data validation (though note that pydantic is less performant than a `TypedDict` or `dataclass`).
The main documented way to specify the schema of a graph is by using `TypedDict`. However, we also support [using a Pydantic BaseModel](../how-tos/graph-api.ipynb#use-pydantic-models-for-graph-state) as your graph state to add **default values** and additional data validation.
By default, the graph will have the same input and output schemas. If you want to change this, you can also specify explicit input and output schemas directly. This is useful when you have a lot of keys, and some are explicitly for input and others for output. See the [guide here](../how-tos/graph-api.md#define-input-and-output-schemas) for how to use.
By default, the graph will have the same input and output schemas. If you want to change this, you can also specify explicit input and output schemas directly. This is useful when you have a lot of keys, and some are explicitly for input and others for output. See the [guide here](../how-tos/graph-api.ipynb#define-input-and-output-schemas) for how to use.
#### Multiple schemas
@@ -56,9 +56,9 @@ Typically, all graph nodes communicate with a single schema. This means that the
- Internal nodes can pass information that is not required in the graph's input / output.
- We may also want to use different input / output schemas for the graph. The output might, for example, only contain a single relevant output key.
It is possible to have nodes write to private state channels inside the graph for internal node communication. We can simply define a private schema, `PrivateState`. See [this guide](../how-tos/graph-api.md#pass-private-state-between-nodes) for more detail.
It is possible to have nodes write to private state channels inside the graph for internal node communication. We can simply define a private schema, `PrivateState`. See [this guide](../how-tos/graph-api.ipynb#pass-private-state-between-nodes) for more detail.
It is also possible to define explicit input and output schemas for a graph. In these cases, we define an "internal" schema that contains _all_ keys relevant to graph operations. But, we also define `input` and `output` schemas that are sub-sets of the "internal" schema to constrain the input and output of the graph. See [this guide](../how-tos/graph-api.md#define-input-and-output-schemas) for more detail.
It is also possible to define explicit input and output schemas for a graph. In these cases, we define an "internal" schema that contains _all_ keys relevant to graph operations. But, we also define `input` and `output` schemas that are sub-sets of the "internal" schema to constrain the input and output of the graph. See [this guide](../how-tos/graph-api.ipynb#define-input-and-output-schemas) for more detail.
Let's look at an example:
@@ -192,48 +192,35 @@ class State(MessagesState):
## Nodes
In LangGraph, nodes are Python functions (either synchronous or asynchronous) that accept the following arguments:
1. `state`: The [state](#state) of the graph
2. `config`: A `RunnableConfig` object that contains configuration information like `thread_id` and tracing information like `tags`
3. `runtime`: A `Runtime` object that contains [runtime `context`](#runtime-context) and other information like `store` and `stream_writer`
In LangGraph, nodes are typically python functions (sync or async) where the **first** positional argument is the [state](#state), and (optionally), the **second** positional argument is a "config", containing optional [configurable parameters](#configuration) (such as a `thread_id`).
Similar to `NetworkX`, you add these nodes to a graph using the [add_node][langgraph.graph.StateGraph.add_node] method:
```python
from dataclasses import dataclass
from typing_extensions import TypedDict
from langchain_core.runnables import RunnableConfig
from langgraph.graph import StateGraph
from langgraph.runtime import Runtime
class State(TypedDict):
input: str
results: str
@dataclass
class Context:
user_id: str
builder = StateGraph(State)
def plain_node(state: State):
def my_node(state: State, config: RunnableConfig):
print("In node: ", config["configurable"]["user_id"])
return {"results": f"Hello, {state['input']}!"}
# The second argument is optional
def my_other_node(state: State):
return state
def node_with_runtime(state: State, runtime: Runtime[Context]):
print("In node: ", runtime.context.user_id)
return {"results": f"Hello, {state['input']}!"}
def node_with_config(state: State, config: RunnableConfig):
print("In node with thread_id: ", config["configurable"]["thread_id"])
return {"results": f"Hello, {state['input']}!"}
builder.add_node("plain_node", plain_node)
builder.add_node("node_with_runtime", node_with_runtime)
builder.add_node("node_with_config", node_with_config)
builder.add_node("my_node", my_node)
builder.add_node("other_node", my_other_node)
...
```
@@ -311,7 +298,7 @@ print(graph.invoke({"x": 5}, stream_mode='updates')) # (2)!
[{'expensive_node': {'result': 10}, '__metadata__': {'cached': True}}]
```
1. First run takes two seconds to run (due to mocked expensive computation).
1. First run takes the full second to run (due to mocked expensive computation).
2. Second run utilizes cache and returns quickly.
## Edges
@@ -419,7 +406,7 @@ def my_node(state: State) -> Command[Literal["my_other_node"]]:
When returning `Command` in your node functions, you must add return type annotations with the list of node names the node is routing to, e.g. `Command[Literal["my_other_node"]]`. This is necessary for the graph rendering and tells LangGraph that `my_node` can navigate to `my_other_node`.
Check out this [how-to guide](../how-tos/graph-api.md#combine-control-flow-and-state-updates-with-command) for an end-to-end example of how to use `Command`.
Check out this [how-to guide](../how-tos/graph-api.ipynb#combine-control-flow-and-state-updates-with-command) for an end-to-end example of how to use `Command`.
### When should I use Command instead of conditional edges?
@@ -446,17 +433,17 @@ def my_node(state: State) -> Command[Literal["other_subgraph"]]:
!!! important "State updates with `Command.PARENT`"
When you send updates from a subgraph node to a parent graph node for a key that's shared by both parent and subgraph [state schemas](#schema), you **must** define a [reducer](#reducers) for the key you're updating in the parent graph state. See this [example](../how-tos/graph-api.md#navigate-to-a-node-in-a-parent-graph).
When you send updates from a subgraph node to a parent graph node for a key that's shared by both parent and subgraph [state schemas](#schema), you **must** define a [reducer](#reducers) for the key you're updating in the parent graph state. See this [example](../how-tos/graph-api.ipynb#navigate-to-a-node-in-a-parent-graph).
This is particularly useful when implementing [multi-agent handoffs](./multi_agent.md#handoffs).
Check out [this guide](../how-tos/graph-api.md#navigate-to-a-node-in-a-parent-graph) for detail.
Check out [this guide](../how-tos/graph-api.ipynb#navigate-to-a-node-in-a-parent-graph) for detail.
### Using inside tools
A common use case is updating graph state from inside a tool. For example, in a customer support application you might want to look up customer information based on their account number or ID in the beginning of the conversation.
Refer to [this guide](../how-tos/graph-api.md#use-inside-tools) for detail.
Refer to [this guide](../how-tos/graph-api.ipynb#use-inside-tools) for detail.
### Human-in-the-loop
@@ -472,47 +459,48 @@ LangGraph can easily handle migrations of graph definitions (nodes, edges, and s
- State keys that are renamed lose their saved state in existing threads
- State keys whose types change in incompatible ways could currently cause issues in threads with state from before the change -- if this is a blocker please reach out and we can prioritize a solution.
## Runtime Context
## Configuration
When creating a graph, you can specify a `context_schema` for runtime context passed to nodes. This is useful for passing
information to nodes that is not part of the graph state. For example, you might want to pass dependencies such as model name or a database connection.
When creating a graph, you can also mark that certain parts of the graph are configurable. This is commonly done to enable easily switching between models or system prompts. This allows you to create a single "cognitive architecture" (the graph) but have multiple different instance of it.
You can optionally specify a `config_schema` when creating a graph.
```python
@dataclass
class ContextSchema:
llm_provider: str = "openai"
class ConfigSchema(TypedDict):
llm: str
graph = StateGraph(State, context_schema=ContextSchema)
graph = StateGraph(State, config_schema=ConfigSchema)
```
You can then pass this context into the graph using the `context` parameter of the `invoke` method.
You can then pass this configuration into the graph using the `configurable` config field.
```python
graph.invoke(inputs, context={"llm_provider": "anthropic"})
config = {"configurable": {"llm": "anthropic"}}
graph.invoke(inputs, config=config)
```
You can then access and use this context inside a node or conditional edge:
You can then access and use this configuration inside a node or conditional edge:
```python
from langgraph.runtime import Runtime
def node_a(state: State, runtime: Runtime[ContextSchema]):
llm = get_llm(runtime.context.llm_provider)
def node_a(state, config):
llm_type = config.get("configurable", {}).get("llm", "openai")
llm = get_llm(llm_type)
...
```
See [this guide](../how-tos/graph-api.md#add-runtime-configuration) for a full breakdown on configuration.
See [this guide](../how-tos/graph-api.ipynb#add-runtime-configuration) for a full breakdown on configuration.
### Recursion Limit
The recursion limit sets the maximum number of [super-steps](#graphs) the graph can execute during a single execution. Once the limit is reached, LangGraph will raise `GraphRecursionError`. By default this value is set to 25 steps. The recursion limit can be set on any graph at runtime, and is passed to `.invoke`/`.stream` via the config dictionary. Importantly, `recursion_limit` is a standalone `config` key and should not be passed inside the `configurable` key as all other user-defined configuration. See the example below:
```python
graph.invoke(inputs, config={"recursion_limit": 5}, context={"llm": "anthropic"})
graph.invoke(inputs, config={"recursion_limit": 5, "configurable":{"llm": "anthropic"}})
```
Read [this how-to](https://langchain-ai.github.io/langgraph/how-tos/recursion-limit/) to learn more about how the recursion limit works.
## Visualization
It's often nice to be able to visualize graphs, especially as they get more complex. LangGraph comes with several built-in ways to visualize graphs. See [this how-to guide](../how-tos/graph-api.md#visualize-your-graph) for more info.
It's often nice to be able to visualize graphs, especially as they get more complex. LangGraph comes with several built-in ways to visualize graphs. See [this how-to guide](../how-tos/graph-api.ipynb#visualize-your-graph) for more info.
-57
View File
@@ -1,57 +0,0 @@
# MCP
[Model Context Protocol (MCP)](https://modelcontextprotocol.io/introduction) is an open protocol that standardizes how applications provide tools and context to language models. LangGraph agents can use tools defined on MCP servers through the `langchain-mcp-adapters` library.
![MCP](../agents/assets/mcp.png)
Install the `langchain-mcp-adapters` library to use MCP tools in LangGraph:
```bash
pip install langchain-mcp-adapters
```
## Authenticate to an MCP server
You can set up [custom authentication middleware](../how-tos/auth/custom_auth.md) to authenticate a user with an MCP server to get access to user-scoped tools within your LangGraph Platform deployment.
!!! note
Custom authentication is a LangGraph Platform feature.
An example architecture for this flow:
```mermaid
sequenceDiagram
%% Actors
participant ClientApp as Client
participant AuthProv as Auth Provider
participant LangGraph as LangGraph Backend
participant SecretStore as Secret Store
participant MCPServer as MCP Server
%% Platform login / AuthN
ClientApp ->> AuthProv: 1. Login (username / password)
AuthProv -->> ClientApp: 2. Return token
ClientApp ->> LangGraph: 3. Request with token
Note over LangGraph: 4. Validate token (@auth.authenticate)
LangGraph -->> AuthProv: 5. Fetch user info
AuthProv -->> LangGraph: 6. Confirm validity
%% Fetch user tokens from secret store
LangGraph ->> SecretStore: 6a. Fetch user tokens
SecretStore -->> LangGraph: 6b. Return tokens
Note over LangGraph: 7. Apply access control (@auth.on.*)
%% MCP round-trip
Note over LangGraph: 8. Build MCP client with user token
LangGraph ->> MCPServer: 9. Call MCP tool (with header)
Note over MCPServer: 10. MCP validates header and runs tool
MCPServer -->> LangGraph: 11. Tool response
%% Return to caller
LangGraph -->> ClientApp: 12. Return resources / tool output
```
For more information, see [MCP endpoint in LangGraph Server](../concepts/server-mcp.md#use-user-scoped-mcp-tools-in-your-deployment).
+272 -128
View File
@@ -5,154 +5,182 @@ search:
# Memory
[Memory](../how-tos/memory/add-memory.md) is a system that remembers information about previous interactions. For AI agents, memory is crucial because it lets them remember previous interactions, learn from feedback, and adapt to user preferences. As agents tackle more complex tasks with numerous user interactions, this capability becomes essential for both efficiency and user satisfaction.
## What is Memory?
This conceptual guide covers two types of memory, based on their recall scope:
[Memory](https://pmc.ncbi.nlm.nih.gov/articles/PMC10410470/) is a cognitive function that allows people to store, retrieve, and use information to understand their present and future. Consider the frustration of working with a colleague who forgets everything you tell them, requiring constant repetition! As AI agents undertake more complex tasks involving numerous user interactions, equipping them with memory becomes equally crucial for efficiency and user satisfaction. With memory, agents can learn from feedback and adapt to users' preferences. This guide covers two types of memory based on recall scope:
- [Short-term memory](#short-term-memory), or [thread](persistence.md#threads)-scoped memory, tracks the ongoing conversation by maintaining message history within a session. LangGraph manages short-term memory as a part of your agent's [state](low_level.md#state). State is persisted to a database using a [checkpointer](persistence.md#checkpoints) so the thread can be resumed at any time. Short-term memory updates when the graph is invoked or a step is completed, and the State is read at the start of each step.
**Short-term memory**, or [thread](persistence.md#threads)-scoped memory, can be recalled at any time **from within** a single conversational thread with a user. LangGraph manages short-term memory as a part of your agent's [state](low_level.md#state). State is persisted to a database using a [checkpointer](persistence.md#checkpoints) so the thread can be resumed at any time. Short-term memory updates when the graph is invoked or a step is completed, and the State is read at the start of each step.
- [Long-term memory](#long-term-memory) stores user-specific or application-level data across sessions and is shared _across_ conversational threads. It can be recalled _at any time_ and _in any thread_. Memories are scoped to any custom namespace, not just within a single thread ID. LangGraph provides [stores](persistence.md#memory-store) ([reference doc](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.BaseStore)) to let you save and recall long-term memories.
**Long-term memory** is shared **across** conversational threads. It can be recalled _at any time_ and **in any thread**. Memories are scoped to any custom namespace, not just within a single thread ID. LangGraph provides [stores](persistence.md#memory-store) ([reference doc](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.BaseStore)) to let you save and recall long-term memories.
Both are important to understand and implement for your application.
![](img/memory/short-vs-long.png)
## Short-term memory
[Short-term memory](../how-tos/memory/add-memory.md#add-short-term-memory) lets your application remember previous interactions within a single [thread](persistence.md#threads) or conversation. A [thread](persistence.md#threads) organizes multiple interactions in a session, similar to the way email groups messages in a single conversation.
Short-term memory lets your application remember previous interactions within a single [thread](persistence.md#threads) or conversation. A [thread](persistence.md#threads) organizes multiple interactions in a session, similar to the way email groups messages in a single conversation.
LangGraph manages short-term memory as part of the agent's state, persisted via thread-scoped checkpoints. This state can normally include the conversation history along with other stateful data, such as uploaded files, retrieved documents, or generated artifacts. By storing these in the graph's state, the bot can access the full context for a given conversation while maintaining separation between different threads.
### Manage short-term memory
Since conversation history is the most common form of representing short-term memory, in the next section, we will cover techniques for managing conversation history when the list of messages becomes **long**. If you want to stick to the high-level concepts, continue on to the [long-term memory](#long-term-memory) section.
Conversation history is the most common form of short-term memory, and long conversations pose a challenge to today's LLMs. A full history may not fit inside an LLM's context window, resulting in an irrecoverable error. Even if your LLM supports the full context length, most LLMs still perform poorly over long contexts. They get "distracted" by stale or off-topic content, all while suffering from slower response times and higher costs.
### Managing long conversation history
Chat models accept context using messages, which include developer provided instructions (a system message) and user inputs (human messages). In chat applications, messages alternate between human inputs and model responses, resulting in a list of messages that grows longer over time. Because context windows are limited and token-rich message lists can be costly, many applications can benefit from using techniques to manually remove or forget stale information.
Long conversations pose a challenge to today's LLMs. The full history may not even fit inside an LLM's context window, resulting in an irrecoverable error. Even _if_ your LLM technically supports the full context length, most LLMs still perform poorly over long contexts. They get "distracted" by stale or off-topic content, all while suffering from slower response times and higher costs.
Managing short-term memory is an exercise of balancing [precision & recall](https://en.wikipedia.org/wiki/Precision_and_recall#:~:text=Precision%20can%20be%20seen%20as,irrelevant%20ones%20are%20also%20returned) with your application's other performance requirements (latency & cost). As always, it's important to think critically about how you represent information for your LLM and to look at your data. We cover a few common techniques for managing message lists below and hope to provide sufficient context for you to pick the best tradeoffs for your application:
- [Editing message lists](#editing-message-lists): How to think about trimming and filtering a list of messages before passing to language model.
- [Summarizing past conversations](#summarizing-past-conversations): A common technique to use when you don't just want to filter the list of messages.
### Editing message lists
Chat models accept context using [messages](https://python.langchain.com/docs/concepts/#messages), which include developer provided instructions (a system message) and user inputs (human messages). In chat applications, messages alternate between human inputs and model responses, resulting in a list of messages that grows longer over time. Because context windows are limited and token-rich message lists can be costly, many applications can benefit from using techniques to manually remove or forget stale information.
![](img/memory/filter.png)
For more information on common techniques for managing messages, see the [Add and manage memory](../how-tos/memory/add-memory.md#manage-short-term-memory) guide.
The most direct approach is to remove old messages from a list (similar to a [least-recently used cache](https://en.wikipedia.org/wiki/Page_replacement_algorithm#Least_recently_used)).
The typical technique for deleting content from a list in LangGraph is to return an update from a node telling the system to delete some portion of the list. You get to define what this update looks like, but a common approach would be to let you return an object or dictionary specifying which values to retain.
```python
def manage_list(existing: list, updates: Union[list, dict]):
if isinstance(updates, list):
# Normal case, add to the history
return existing + updates
elif isinstance(updates, dict) and updates["type"] == "keep":
# You get to decide what this looks like.
# For example, you could simplify and just accept a string "DELETE"
# and clear the entire list.
return existing[updates["from"]:updates["to"]]
# etc. We define how to interpret updates
class State(TypedDict):
my_list: Annotated[list, manage_list]
def my_node(state: State):
return {
# We return an update for the field "my_list" saying to
# keep only values from index -5 to the end (deleting the rest)
"my_list": {"type": "keep", "from": -5, "to": None}
}
```
LangGraph will call the `manage_list` "[reducer](low_level.md#reducers)" function any time an update is returned under the key "my_list". Within that function, we define what types of updates to accept. Typically, messages will be added to the existing list (the conversation will grow); however, we've also added support to accept a dictionary that lets you "keep" certain parts of the state. This lets you programmatically drop old message context.
Another common approach is to let you return a list of "remove" objects that specify the IDs of all messages to delete. If you're using the LangChain messages and the [`add_messages`](https://langchain-ai.github.io/langgraph/reference/graphs/#langgraph.graph.message.add_messages) reducer (or `MessagesState`, which uses the same underlying functionality) in LangGraph, you can do this using a `RemoveMessage`.
```python
from langchain_core.messages import RemoveMessage, AIMessage
from langgraph.graph import add_messages
# ... other imports
class State(TypedDict):
# add_messages will default to upserting messages by ID to the existing list
# if a RemoveMessage is returned, it will delete the message in the list by ID
messages: Annotated[list, add_messages]
def my_node_1(state: State):
# Add an AI message to the `messages` list in the state
return {"messages": [AIMessage(content="Hi")]}
def my_node_2(state: State):
# Delete all but the last 2 messages from the `messages` list in the state
delete_messages = [RemoveMessage(id=m.id) for m in state['messages'][:-2]]
return {"messages": delete_messages}
```
In the example above, the `add_messages` reducer allows us to [append](https://langchain-ai.github.io/langgraph/concepts/low_level/#serialization) new messages to the `messages` state key as shown in `my_node_1`. When it sees a `RemoveMessage`, it will delete the message with that ID from the list (and the RemoveMessage will then be discarded). For more information on LangChain-specific message handling, check out [this how-to on using `RemoveMessage` ](https://langchain-ai.github.io/langgraph/how-tos/memory/delete-messages/).
See this how-to [guide](https://langchain-ai.github.io/langgraph/how-tos/memory/manage-conversation-history/) and module 2 from our [LangChain Academy](https://github.com/langchain-ai/langchain-academy/tree/main/module-2) course for example usage.
### Summarizing past conversations
The problem with trimming or removing messages, as shown above, is that we may lose information from culling of the message queue. Because of this, some applications benefit from a more sophisticated approach of summarizing the message history using a chat model.
![](img/memory/summary.png)
Simple prompting and orchestration logic can be used to achieve this. As an example, in LangGraph we can extend the [MessagesState](https://langchain-ai.github.io/langgraph/concepts/low_level/#working-with-messages-in-graph-state) to include a `summary` key.
```python
from langgraph.graph import MessagesState
class State(MessagesState):
summary: str
```
Then, we can generate a summary of the chat history, using any existing summary as context for the next summary. This `summarize_conversation` node can be called after some number of messages have accumulated in the `messages` state key.
```python
def summarize_conversation(state: State):
# First, we get any existing summary
summary = state.get("summary", "")
# Create our summarization prompt
if summary:
# A summary already exists
summary_message = (
f"This is a summary of the conversation to date: {summary}\n\n"
"Extend the summary by taking into account the new messages above:"
)
else:
summary_message = "Create a summary of the conversation above:"
# Add prompt to our history
messages = state["messages"] + [HumanMessage(content=summary_message)]
response = model.invoke(messages)
# Delete all but the 2 most recent messages
delete_messages = [RemoveMessage(id=m.id) for m in state["messages"][:-2]]
return {"summary": response.content, "messages": delete_messages}
```
See this how-to [here](https://langchain-ai.github.io/langgraph/how-tos/memory/add-summary-conversation-history/) and module 2 from our [LangChain Academy](https://github.com/langchain-ai/langchain-academy/tree/main/module-2) course for example usage.
### Knowing **when** to remove messages
Most LLMs have a maximum supported context window (denominated in tokens). A simple way to decide when to truncate messages is to count the tokens in the message history and truncate whenever it approaches that limit. Naive truncation is straightforward to implement on your own, though there are a few "gotchas". Some model APIs further restrict the sequence of message types (must start with human message, cannot have consecutive messages of the same type, etc.). If you're using LangChain, you can use the [`trim_messages`](https://python.langchain.com/docs/how_to/trim_messages/#trimming-based-on-token-count) utility and specify the number of tokens to keep from the list, as well as the `strategy` (e.g., keep the last `max_tokens`) to use for handling the boundary.
Below is an example.
```python
from langchain_core.messages import trim_messages
trim_messages(
messages,
# Keep the last <= n_count tokens of the messages.
strategy="last",
# Remember to adjust based on your model
# or else pass a custom token_encoder
token_counter=ChatOpenAI(model="gpt-4"),
# Remember to adjust based on the desired conversation
# length
max_tokens=45,
# Most chat models expect that chat history starts with either:
# (1) a HumanMessage or
# (2) a SystemMessage followed by a HumanMessage
start_on="human",
# Most chat models expect that chat history ends with either:
# (1) a HumanMessage or
# (2) a ToolMessage
end_on=("human", "tool"),
# Usually, we want to keep the SystemMessage
# if it's present in the original history.
# The SystemMessage has special instructions for the model.
include_system=True,
)
```
## Long-term memory
[Long-term memory](../how-tos/memory/add-memory.md#add-long-term-memory) in LangGraph allows systems to retain information across different conversations or sessions. Unlike short-term memory, which is **thread-scoped**, long-term memory is saved within custom "namespaces."
Long-term memory in LangGraph allows systems to retain information across different conversations or sessions. Unlike short-term memory, which is **thread-scoped**, long-term memory is saved within custom "namespaces."
Long-term memory is a complex challenge without a one-size-fits-all solution. However, the following questions provide a framework to help you navigate the different techniques:
### Storing memories
- [What is the type of memory?](#memory-types) Humans use memories to remember facts ([semantic memory](#semantic-memory)), experiences ([episodic memory](#episodic-memory)), and rules ([procedural memory](#procedural-memory)). AI agents can use memory in the same ways. For example, AI agents can use memory to remember specific facts about a user to accomplish a task.
- [When do you want to update memories?](#writing-memories) Memory can be updated as part of an agent's application logic (e.g., "on the hot path"). In this case, the agent typically decides to remember facts before responding to a user. Alternatively, memory can be updated as a background task (logic that runs in the background / asynchronously and generates memories). We explain the tradeoffs between these approaches in the [section below](#writing-memories).
### Memory types
Different applications require various types of memory. Although the analogy isn't perfect, examining [human memory types](https://www.psychologytoday.com/us/basics/memory/types-of-memory?ref=blog.langchain.dev) can be insightful. Some research (e.g., the [CoALA paper](https://arxiv.org/pdf/2309.02427)) have even mapped these human memory types to those used in AI agents.
| Memory Type | What is Stored | Human Example | Agent Example |
|-------------|----------------|---------------|---------------|
| [Semantic](#semantic-memory) | Facts | Things I learned in school | Facts about a user |
| [Episodic](#episodic-memory) | Experiences | Things I did | Past agent actions |
| [Procedural](#procedural-memory) | Instructions | Instincts or motor skills | Agent system prompt |
#### Semantic memory
[Semantic memory](https://en.wikipedia.org/wiki/Semantic_memory), both in humans and AI agents, involves the retention of specific facts and concepts. In humans, it can include information learned in school and the understanding of concepts and their relationships. For AI agents, semantic memory is often used to personalize applications by remembering facts or concepts from past interactions.
!!! note
Semantic memory is different from "semantic search," which is a technique for finding similar content using "meaning" (usually as embeddings). Semantic memory is a term from psychology, referring to storing facts and knowledge, while semantic search is a method for retrieving information based on meaning rather than exact matches.
##### Profile
Semantic memories can be managed in different ways. For example, memories can be a single, continuously updated "profile" of well-scoped and specific information about a user, organization, or other entity (including the agent itself). A profile is generally just a JSON document with various key-value pairs you've selected to represent your domain.
When remembering a profile, you will want to make sure that you are **updating** the profile each time. As a result, you will want to pass in the previous profile and [ask the model to generate a new profile](https://github.com/langchain-ai/memory-template) (or some [JSON patch](https://github.com/hinthornw/trustcall) to apply to the old profile). This can be become error-prone as the profile gets larger, and may benefit from splitting a profile into multiple documents or **strict** decoding when generating documents to ensure the memory schemas remains valid.
![](img/memory/update-profile.png)
##### Collection
Alternatively, memories can be a collection of documents that are continuously updated and extended over time. Each individual memory can be more narrowly scoped and easier to generate, which means that you're less likely to **lose** information over time. It's easier for an LLM to generate _new_ objects for new information than reconcile new information with an existing profile. As a result, a document collection tends to lead to [higher recall downstream](https://en.wikipedia.org/wiki/Precision_and_recall).
However, this shifts some complexity memory updating. The model must now _delete_ or _update_ existing items in the list, which can be tricky. In addition, some models may default to over-inserting and others may default to over-updating. See the [Trustcall](https://github.com/hinthornw/trustcall) package for one way to manage this and consider evaluation (e.g., with a tool like [LangSmith](https://docs.smith.langchain.com/tutorials/Developers/evaluation)) to help you tune the behavior.
Working with document collections also shifts complexity to memory **search** over the list. The `Store` currently supports both [semantic search](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.SearchOp.query) and [filtering by content](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.SearchOp.filter).
Finally, using a collection of memories can make it challenging to provide comprehensive context to the model. While individual memories may follow a specific schema, this structure might not capture the full context or relationships between memories. As a result, when using these memories to generate responses, the model may lack important contextual information that would be more readily available in a unified profile approach.
![](img/memory/update-list.png)
Regardless of memory management approach, the central point is that the agent will use the semantic memories to [ground its responses](https://python.langchain.com/docs/concepts/rag/), which often leads to more personalized and relevant interactions.
#### Episodic memory
[Episodic memory](https://en.wikipedia.org/wiki/Episodic_memory), in both humans and AI agents, involves recalling past events or actions. The [CoALA paper](https://arxiv.org/pdf/2309.02427) frames this well: facts can be written to semantic memory, whereas *experiences* can be written to episodic memory. For AI agents, episodic memory is often used to help an agent remember how to accomplish a task.
In practice, episodic memories are often implemented through [few-shot example prompting](https://python.langchain.com/docs/concepts/few_shot_prompting/), where agents learn from past sequences to perform tasks correctly. Sometimes it's easier to "show" than "tell" and LLMs learn well from examples. Few-shot learning lets you ["program"](https://x.com/karpathy/status/1627366413840322562) your LLM by updating the prompt with input-output examples to illustrate the intended behavior. While various [best-practices](https://python.langchain.com/docs/concepts/#1-generating-examples) can be used to generate few-shot examples, often the challenge lies in selecting the most relevant examples based on user input.
Note that the memory [store](persistence.md#memory-store) is just one way to store data as few-shot examples. If you want to have more developer involvement, or tie few-shots more closely to your evaluation harness, you can also use a [LangSmith Dataset](https://docs.smith.langchain.com/evaluation/how_to_guides/datasets/index_datasets_for_dynamic_few_shot_example_selection) to store your data. Then dynamic few-shot example selectors can be used out-of-the box to achieve this same goal. LangSmith will index the dataset for you and enable retrieval of few shot examples that are most relevant to the user input based upon keyword similarity ([using a BM25-like algorithm](https://docs.smith.langchain.com/how_to_guides/datasets/index_datasets_for_dynamic_few_shot_example_selection) for keyword based similarity).
See this how-to [video](https://www.youtube.com/watch?v=37VaU7e7t5o) for example usage of dynamic few-shot example selection in LangSmith. Also, see this [blog post](https://blog.langchain.dev/few-shot-prompting-to-improve-tool-calling-performance/) showcasing few-shot prompting to improve tool calling performance and this [blog post](https://blog.langchain.dev/aligning-llm-as-a-judge-with-human-preferences/) using few-shot example to align an LLMs to human preferences.
#### Procedural memory
[Procedural memory](https://en.wikipedia.org/wiki/Procedural_memory), in both humans and AI agents, involves remembering the rules used to perform tasks. In humans, procedural memory is like the internalized knowledge of how to perform tasks, such as riding a bike via basic motor skills and balance. Episodic memory, on the other hand, involves recalling specific experiences, such as the first time you successfully rode a bike without training wheels or a memorable bike ride through a scenic route. For AI agents, procedural memory is a combination of model weights, agent code, and agent's prompt that collectively determine the agent's functionality.
In practice, it is fairly uncommon for agents to modify their model weights or rewrite their code. However, it is more common for agents to modify their own prompts.
One effective approach to refining an agent's instructions is through ["Reflection"](https://blog.langchain.dev/reflection-agents/) or meta-prompting. This involves prompting the agent with its current instructions (e.g., the system prompt) along with recent conversations or explicit user feedback. The agent then refines its own instructions based on this input. This method is particularly useful for tasks where instructions are challenging to specify upfront, as it allows the agent to learn and adapt from its interactions.
For example, we built a [Tweet generator](https://www.youtube.com/watch?v=Vn8A3BxfplE) using external feedback and prompt re-writing to produce high-quality paper summaries for Twitter. In this case, the specific summarization prompt was difficult to specify *a priori*, but it was fairly easy for a user to critique the generated Tweets and provide feedback on how to improve the summarization process.
The below pseudo-code shows how you might implement this with the LangGraph memory [store](persistence.md#memory-store), using the store to save a prompt, the `update_instructions` node to get the current prompt (as well as feedback from the conversation with the user captured in `state["messages"]`), update the prompt, and save the new prompt back to the store. Then, the `call_model` get the updated prompt from the store and uses it to generate a response.
```python
# Node that *uses* the instructions
def call_model(state: State, store: BaseStore):
namespace = ("agent_instructions", )
instructions = store.get(namespace, key="agent_a")[0]
# Application logic
prompt = prompt_template.format(instructions=instructions.value["instructions"])
...
# Node that updates instructions
def update_instructions(state: State, store: BaseStore):
namespace = ("instructions",)
current_instructions = store.search(namespace)[0]
# Memory logic
prompt = prompt_template.format(instructions=instructions.value["instructions"], conversation=state["messages"])
output = llm.invoke(prompt)
new_instructions = output['new_instructions']
store.put(("agent_instructions",), "agent_a", {"instructions": new_instructions})
...
```
![](img/memory/update-instructions.png)
### Writing memories
There are two primary methods for agents to write memories: ["in the hot path"](#in-the-hot-path) and ["in the background"](#in-the-background).
![](img/memory/hot_path_vs_background.png)
#### In the hot path
Creating memories during runtime offers both advantages and challenges. On the positive side, this approach allows for real-time updates, making new memories immediately available for use in subsequent interactions. It also enables transparency, as users can be notified when memories are created and stored.
However, this method also presents challenges. It may increase complexity if the agent requires a new tool to decide what to commit to memory. In addition, the process of reasoning about what to save to memory can impact agent latency. Finally, the agent must multitask between memory creation and its other responsibilities, potentially affecting the quantity and quality of memories created.
As an example, ChatGPT uses a [save_memories](https://openai.com/index/memory-and-new-controls-for-chatgpt/) tool to upsert memories as content strings, deciding whether and how to use this tool with each user message. See our [memory-agent](https://github.com/langchain-ai/memory-agent) template as an reference implementation.
#### In the background
Creating memories as a separate background task offers several advantages. It eliminates latency in the primary application, separates application logic from memory management, and allows for more focused task completion by the agent. This approach also provides flexibility in timing memory creation to avoid redundant work.
However, this method has its own challenges. Determining the frequency of memory writing becomes crucial, as infrequent updates may leave other threads without new context. Deciding when to trigger memory formation is also important. Common strategies include scheduling after a set time period (with rescheduling if new events occur), using a cron schedule, or allowing manual triggers by users or the application logic.
See our [memory-service](https://github.com/langchain-ai/memory-template) template as an reference implementation.
### Memory storage
LangGraph stores long-term memories as JSON documents in a [store](persistence.md#memory-store). Each memory is organized under a custom `namespace` (similar to a folder) and a distinct `key` (like a file name). Namespaces often include user or org IDs or other labels that makes it easier to organize information. This structure enables hierarchical organization of memories. Cross-namespace searching is then supported through content filters.
LangGraph stores long-term memories as JSON documents in a [store](persistence.md#memory-store) ([reference doc](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.BaseStore)). Each memory is organized under a custom `namespace` (similar to a folder) and a distinct `key` (like a filename). Namespaces often include user or org IDs or other labels that makes it easier to organize information. This structure enables hierarchical organization of memories. Cross-namespace searching is then supported through content filters. See the example below for an example.
```python
from langgraph.store.memory import InMemoryStore
@@ -187,4 +215,120 @@ items = store.search(
)
```
For more information about the memory store, see the [Persistence](persistence.md#memory-store) guide.
### Framework for thinking about long-term memory
Long-term memory is a complex challenge without a one-size-fits-all solution. However, the following questions provide a structure framework to help you navigate the different techniques:
**What is the type of memory?**
Humans use memories to remember [facts](https://en.wikipedia.org/wiki/Semantic_memory), [experiences](https://en.wikipedia.org/wiki/Episodic_memory), and [rules](https://en.wikipedia.org/wiki/Procedural_memory). AI agents can use memory in the same ways. For example, AI agents can use memory to remember specific facts about a user to accomplish a task. We expand on several types of memories in the [section below](#memory-types).
**When do you want to update memories?**
Memory can be updated as part of an agent's application logic (e.g. "on the hot path"). In this case, the agent typically decides to remember facts before responding to a user. Alternatively, memory can be updated as a background task (logic that runs in the background / asynchronously and generates memories). We explain the tradeoffs between these approaches in the [section below](#writing-memories).
## Memory types
Different applications require various types of memory. Although the analogy isn't perfect, examining [human memory types](https://www.psychologytoday.com/us/basics/memory/types-of-memory?ref=blog.langchain.dev) can be insightful. Some research (e.g., the [CoALA paper](https://arxiv.org/pdf/2309.02427)) have even mapped these human memory types to those used in AI agents.
| Memory Type | What is Stored | Human Example | Agent Example |
|-------------|----------------|---------------|---------------|
| Semantic | Facts | Things I learned in school | Facts about a user |
| Episodic | Experiences | Things I did | Past agent actions |
| Procedural | Instructions | Instincts or motor skills | Agent system prompt |
### Semantic Memory
[Semantic memory](https://en.wikipedia.org/wiki/Semantic_memory), both in humans and AI agents, involves the retention of specific facts and concepts. In humans, it can include information learned in school and the understanding of concepts and their relationships. For AI agents, semantic memory is often used to personalize applications by remembering facts or concepts from past interactions.
> Note: Not to be confused with "semantic search" which is a technique for finding similar content using "meaning" (usually as embeddings). Semantic memory is a term from psychology, referring to storing facts and knowledge, while semantic search is a method for retrieving information based on meaning rather than exact matches.
#### Profile
Semantic memories can be managed in different ways. For example, memories can be a single, continuously updated "profile" of well-scoped and specific information about a user, organization, or other entity (including the agent itself). A profile is generally just a JSON document with various key-value pairs you've selected to represent your domain.
When remembering a profile, you will want to make sure that you are **updating** the profile each time. As a result, you will want to pass in the previous profile and [ask the model to generate a new profile](https://github.com/langchain-ai/memory-template) (or some [JSON patch](https://github.com/hinthornw/trustcall) to apply to the old profile). This can be become error-prone as the profile gets larger, and may benefit from splitting a profile into multiple documents or **strict** decoding when generating documents to ensure the memory schemas remains valid.
![](img/memory/update-profile.png)
#### Collection
Alternatively, memories can be a collection of documents that are continuously updated and extended over time. Each individual memory can be more narrowly scoped and easier to generate, which means that you're less likely to **lose** information over time. It's easier for an LLM to generate _new_ objects for new information than reconcile new information with an existing profile. As a result, a document collection tends to lead to [higher recall downstream](https://en.wikipedia.org/wiki/Precision_and_recall).
However, this shifts some complexity memory updating. The model must now _delete_ or _update_ existing items in the list, which can be tricky. In addition, some models may default to over-inserting and others may default to over-updating. See the [Trustcall](https://github.com/hinthornw/trustcall) package for one way to manage this and consider evaluation (e.g., with a tool like [LangSmith](https://docs.smith.langchain.com/tutorials/Developers/evaluation)) to help you tune the behavior.
Working with document collections also shifts complexity to memory **search** over the list. The `Store` currently supports both [semantic search](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.SearchOp.query) and [filtering by content](https://langchain-ai.github.io/langgraph/reference/store/#langgraph.store.base.SearchOp.filter).
Finally, using a collection of memories can make it challenging to provide comprehensive context to the model. While individual memories may follow a specific schema, this structure might not capture the full context or relationships between memories. As a result, when using these memories to generate responses, the model may lack important contextual information that would be more readily available in a unified profile approach.
![](img/memory/update-list.png)
Regardless of memory management approach, the central point is that the agent will use the semantic memories to [ground its responses](https://python.langchain.com/docs/concepts/rag/), which often leads to more personalized and relevant interactions.
### Episodic Memory
[Episodic memory](https://en.wikipedia.org/wiki/Episodic_memory), in both humans and AI agents, involves recalling past events or actions. The [CoALA paper](https://arxiv.org/pdf/2309.02427) frames this well: facts can be written to semantic memory, whereas *experiences* can be written to episodic memory. For AI agents, episodic memory is often used to help an agent remember how to accomplish a task.
In practice, episodic memories are often implemented through [few-shot example prompting](https://python.langchain.com/docs/concepts/few_shot_prompting/), where agents learn from past sequences to perform tasks correctly. Sometimes it's easier to "show" than "tell" and LLMs learn well from examples. Few-shot learning lets you ["program"](https://x.com/karpathy/status/1627366413840322562) your LLM by updating the prompt with input-output examples to illustrate the intended behavior. While various [best-practices](https://python.langchain.com/docs/concepts/#1-generating-examples) can be used to generate few-shot examples, often the challenge lies in selecting the most relevant examples based on user input.
Note that the memory [store](persistence.md#memory-store) is just one way to store data as few-shot examples. If you want to have more developer involvement, or tie few-shots more closely to your evaluation harness, you can also use a [LangSmith Dataset](https://docs.smith.langchain.com/evaluation/how_to_guides/datasets/index_datasets_for_dynamic_few_shot_example_selection) to store your data. Then dynamic few-shot example selectors can be used out-of-the box to achieve this same goal. LangSmith will index the dataset for you and enable retrieval of few shot examples that are most relevant to the user input based upon keyword similarity ([using a BM25-like algorithm](https://docs.smith.langchain.com/how_to_guides/datasets/index_datasets_for_dynamic_few_shot_example_selection) for keyword based similarity).
See this how-to [video](https://www.youtube.com/watch?v=37VaU7e7t5o) for example usage of dynamic few-shot example selection in LangSmith. Also, see this [blog post](https://blog.langchain.dev/few-shot-prompting-to-improve-tool-calling-performance/) showcasing few-shot prompting to improve tool calling performance and this [blog post](https://blog.langchain.dev/aligning-llm-as-a-judge-with-human-preferences/) using few-shot example to align an LLMs to human preferences.
### Procedural Memory
[Procedural memory](https://en.wikipedia.org/wiki/Procedural_memory), in both humans and AI agents, involves remembering the rules used to perform tasks. In humans, procedural memory is like the internalized knowledge of how to perform tasks, such as riding a bike via basic motor skills and balance. Episodic memory, on the other hand, involves recalling specific experiences, such as the first time you successfully rode a bike without training wheels or a memorable bike ride through a scenic route. For AI agents, procedural memory is a combination of model weights, agent code, and agent's prompt that collectively determine the agent's functionality.
In practice, it is fairly uncommon for agents to modify their model weights or rewrite their code. However, it is more common for agents to modify their own prompts.
One effective approach to refining an agent's instructions is through ["Reflection"](https://blog.langchain.dev/reflection-agents/) or meta-prompting. This involves prompting the agent with its current instructions (e.g., the system prompt) along with recent conversations or explicit user feedback. The agent then refines its own instructions based on this input. This method is particularly useful for tasks where instructions are challenging to specify upfront, as it allows the agent to learn and adapt from its interactions.
For example, we built a [Tweet generator](https://www.youtube.com/watch?v=Vn8A3BxfplE) using external feedback and prompt re-writing to produce high-quality paper summaries for Twitter. In this case, the specific summarization prompt was difficult to specify *a priori*, but it was fairly easy for a user to critique the generated Tweets and provide feedback on how to improve the summarization process.
The below pseudo-code shows how you might implement this with the LangGraph memory [store](persistence.md#memory-store), using the store to save a prompt, the `update_instructions` node to get the current prompt (as well as feedback from the conversation with the user captured in `state["messages"]`), update the prompt, and save the new prompt back to the store. Then, the `call_model` get the updated prompt from the store and uses it to generate a response.
```python
# Node that *uses* the instructions
def call_model(state: State, store: BaseStore):
namespace = ("agent_instructions", )
instructions = store.get(namespace, key="agent_a")[0]
# Application logic
prompt = prompt_template.format(instructions=instructions.value["instructions"])
...
# Node that updates instructions
def update_instructions(state: State, store: BaseStore):
namespace = ("instructions",)
current_instructions = store.search(namespace)[0]
# Memory logic
prompt = prompt_template.format(instructions=instructions.value["instructions"], conversation=state["messages"])
output = llm.invoke(prompt)
new_instructions = output['new_instructions']
store.put(("agent_instructions",), "agent_a", {"instructions": new_instructions})
...
```
![](img/memory/update-instructions.png)
## Writing memories
While [humans often form long-term memories during sleep](https://medicine.yale.edu/news-article/sleeps-crucial-role-in-preserving-memory/), AI agents need a different approach. When and how should agents create new memories? There are at least two primary methods for agents to write memories: "on the hot path" and "in the background".
![](img/memory/hot_path_vs_background.png)
### Writing memories in the hot path
Creating memories during runtime offers both advantages and challenges. On the positive side, this approach allows for real-time updates, making new memories immediately available for use in subsequent interactions. It also enables transparency, as users can be notified when memories are created and stored.
However, this method also presents challenges. It may increase complexity if the agent requires a new tool to decide what to commit to memory. In addition, the process of reasoning about what to save to memory can impact agent latency. Finally, the agent must multitask between memory creation and its other responsibilities, potentially affecting the quantity and quality of memories created.
As an example, ChatGPT uses a [save_memories](https://openai.com/index/memory-and-new-controls-for-chatgpt/) tool to upsert memories as content strings, deciding whether and how to use this tool with each user message. See our [memory-agent](https://github.com/langchain-ai/memory-agent) template as an reference implementation.
### Writing memories in the background
Creating memories as a separate background task offers several advantages. It eliminates latency in the primary application, separates application logic from memory management, and allows for more focused task completion by the agent. This approach also provides flexibility in timing memory creation to avoid redundant work.
However, this method has its own challenges. Determining the frequency of memory writing becomes crucial, as infrequent updates may leave other threads without new context. Deciding when to trigger memory formation is also important. Common strategies include scheduling after a set time period (with rescheduling if new events occur), using a cron schedule, or allowing manual triggers by users or the application logic.
See our [memory-service](https://github.com/langchain-ai/memory-template) template as an reference implementation.
+7 -8
View File
@@ -26,7 +26,7 @@ The primary benefits of using multi-agent systems are:
There are several ways to connect agents in a multi-agent system:
- **Network**: each agent can communicate with [every other agent](https://langchain-ai.github.io/langgraph/tutorials/multi_agent/multi-agent-collaboration/). Any agent can decide which other agent to call next.
- **Supervisor**: each agent communicates with a single [supervisor](../tutorials/multi_agent/agent_supervisor.md) agent. Supervisor agent makes decisions on which agent should be called next.
- **Supervisor**: each agent communicates with a single [supervisor](https://langchain-ai.github.io/langgraph/tutorials/multi_agent/agent_supervisor/) agent. Supervisor agent makes decisions on which agent should be called next.
- **Supervisor (tool-calling)**: this is a special case of supervisor architecture. Individual agents can be represented as tools. In this case, a supervisor agent uses a tool-calling LLM to decide which of the agent tools to call, as well as the arguments to pass to those agents.
- **Hierarchical**: you can define a multi-agent system with [a supervisor of supervisors](https://langchain-ai.github.io/langgraph/tutorials/multi_agent/hierarchical_agent_teams/). This is a generalization of the supervisor architecture and allows for more complex control flows.
- **Custom multi-agent workflow**: each agent communicates with only a subset of agents. Parts of the flow are deterministic, and only some agents can decide which other agents to call next.
@@ -87,7 +87,6 @@ One of the most common agent types is a [tool-calling agent](../agents/overview.
```python
from langchain_core.tools import tool
@tool
def transfer_to_bob():
"""Transfer to bob."""
return Command(
@@ -166,7 +165,7 @@ network = builder.compile()
### Supervisor
In this architecture, we define agents as nodes and add a supervisor node (LLM) that decides which agent nodes should be called next. We use [`Command`](./low_level.md#command) to route execution to the appropriate agent node based on supervisor's decision. This architecture also lends itself well to running multiple agents in parallel or using [map-reduce](../how-tos/graph-api.md#map-reduce-and-the-send-api) pattern.
In this architecture, we define agents as nodes and add a supervisor node (LLM) that decides which agent nodes should be called next. We use [`Command`](./low_level.md#command) to route execution to the appropriate agent node based on supervisor's decision. This architecture also lends itself well to running multiple agents in parallel or using [map-reduce](../how-tos/graph-api.ipynb#map-reduce-and-the-send-api) pattern.
```python
from typing import Literal
@@ -211,7 +210,7 @@ builder.add_edge(START, "supervisor")
supervisor = builder.compile()
```
Check out this [tutorial](../tutorials/multi_agent/agent_supervisor.md) for an example of supervisor multi-agent architecture.
Check out this [tutorial](https://langchain-ai.github.io/langgraph/tutorials/multi_agent/agent_supervisor/) for an example of supervisor multi-agent architecture.
### Supervisor (tool-calling)
@@ -376,13 +375,13 @@ The most common way for agents to communicate is via a shared state channel, typ
#### Sharing full thought process
Agents can **share the full history** of their thought process (i.e., "scratchpad") with all other agents. This "scratchpad" would typically look like a [list of messages](./low_level.md#why-use-messages). The benefit of sharing the full thought process is that it might help other agents make better decisions and improve reasoning ability for the system as a whole. The downside is that as the number of agents and their complexity grows, the "scratchpad" will grow quickly and might require additional strategies for [memory management](../how-tos/memory/add-memory.md).
Agents can **share the full history** of their thought process (i.e., "scratchpad") with all other agents. This "scratchpad" would typically look like a [list of messages](./low_level.md#why-use-messages). The benefit of sharing the full thought process is that it might help other agents make better decisions and improve reasoning ability for the system as a whole. The downside is that as the number of agents and their complexity grows, the "scratchpad" will grow quickly and might require additional strategies for [memory management](./memory.md/#managing-long-conversation-history).
#### Sharing only final results
Agents can have their own private "scratchpad" and only **share the final result** with the rest of the agents. This approach might work better for systems with many agents or agents that are more complex. In this case, you would need to define agents with [different state schemas](#using-different-state-schemas).
For agents called as tools, the supervisor determines the inputs based on the tool schema. Additionally, LangGraph allows [passing state](../how-tos/tool-calling.md#short-term-memory) to individual tools at runtime, so subordinate agents can access parent state, if needed.
For agents called as tools, the supervisor determines the inputs based on the tool schema. Additionally, LangGraph allows [passing state](../how-tos/tool-calling.ipynb#read-state) to individual tools at runtime, so subordinate agents can access parent state, if needed.
#### Indicating agent name in messages
@@ -414,5 +413,5 @@ There are two high-level approaches to achieve that:
An agent might need to have a different state schema from the rest of the agents. For example, a search agent might only need to keep track of queries and retrieved documents. There are two ways to achieve this in LangGraph:
- Define [subgraph](./subgraphs.md) agents with a separate state schema. If there are no shared state keys (channels) between the subgraph and the parent graph, its important to [add input / output transformations](../how-tos/subgraph.md#different-state-schemas) so that the parent graph knows how to communicate with the subgraphs.
- Define agent node functions with a [private input state schema](../how-tos/graph-api.md/#pass-private-state-between-nodes) that is distinct from the overall graph state schema. This allows passing information that is only needed for executing that particular agent.
- Define [subgraph](./subgraphs.md) agents with a separate state schema. If there are no shared state keys (channels) between the subgraph and the parent graph, its important to [add input / output transformations](../how-tos/subgraph.ipynb#different-state-schemas) so that the parent graph knows how to communicate with the subgraphs.
- Define agent node functions with a [private input state schema](../how-tos/graph-api.ipynb/#pass-private-state-between-nodes) that is distinct from the overall graph state schema. This allows passing information that is only needed for executing that particular agent.
+10 -10
View File
@@ -5,7 +5,7 @@ search:
# Persistence
LangGraph has a built-in persistence layer, implemented through checkpointers. When you compile a graph with a checkpointer, the checkpointer saves a `checkpoint` of the graph state at every super-step. Those checkpoints are saved to a `thread`, which can be accessed after graph execution. Because `threads` allow access to graph's state after execution, several powerful capabilities including human-in-the-loop, memory, time travel, and fault-tolerance are all possible. Below, we'll discuss each of these concepts in more detail.
LangGraph has a built-in persistence layer, implemented through checkpointers. When you compile graph with a checkpointer, the checkpointer saves a `checkpoint` of the graph state at every super-step. Those checkpoints are saved to a `thread`, which can be accessed after graph execution. Because `threads` allow access to graph's state after execution, several powerful capabilities including human-in-the-loop, memory, time travel, and fault-tolerance are all possible. See [this how-to guide](../how-tos/persistence.ipynb) for an end-to-end example on how to add and use checkpointers with your graph. Below, we'll discuss each of these concepts in more detail.
![Checkpoints](img/persistence/checkpoints.jpg)
@@ -15,7 +15,7 @@ LangGraph has a built-in persistence layer, implemented through checkpointers. W
## Threads
A thread is a unique ID or thread identifier assigned to each checkpoint saved by a checkpointer. It contains the accumulated state of a sequence of [runs](./assistants.md#execution). When a run is executed, the [state](../concepts/low_level.md#state) of the underlying graph of the assistant will be persisted to the thread.
A thread is a unique ID or thread identifier assigned to each checkpoint saved by a checkpointer. It contains the accumulated state of a sequence of [runs](../cloud/concepts/runs.md). When a run is executed, the [state](../concepts/low_level.md#state) of the underlying graph of the assistant will be persisted to the thread.
When invoking graph with a checkpointer, you **must** specify a `thread_id` as part of the `configurable` portion of the config:
@@ -33,7 +33,7 @@ The state of a thread at a particular point in time is called a checkpoint. Chec
- `metadata`: Metadata associated with this checkpoint.
- `values`: Values of the state channels at this point in time.
- `next` A tuple of the node names to execute next in the graph.
- `tasks`: A tuple of `PregelTask` objects that contain information about next tasks to be executed. If the step was previously attempted, it will include error information. If a graph was interrupted [dynamically](../how-tos/human_in_the_loop/add-human-in-the-loop.md#pause-using-interrupt) from within a node, tasks will contain additional data associated with interrupts.
- `tasks`: A tuple of `PregelTask` objects that contain information about next tasks to be executed. If the step was previously attempted, it will include error information. If a graph was interrupted [dynamically](../how-tos/human_in_the_loop/breakpoints.ipynb#dynamic-breakpoints) from within a node, tasks will contain additional data associated with interrupts.
Checkpoints are persisted and can be used to restore the state of a thread at a later time.
@@ -78,7 +78,7 @@ After we run the graph, we expect to see exactly 4 checkpoints:
* checkpoint with the outputs of `node_a` `{'foo': 'a', 'bar': ['a']}` and `node_b` as the next node to be executed
* checkpoint with the outputs of `node_b` `{'foo': 'b', 'bar': ['a', 'b']}` and no next nodes to be executed
Note that the `bar` channel values contain outputs from both nodes as we have a reducer for `bar` channel.
Note that we `bar` channel values contain outputs from both nodes as we have a reducer for `bar` channel.
### Get state
@@ -174,7 +174,7 @@ config = {"configurable": {"thread_id": "1", "checkpoint_id": "0c62ca34-ac19-445
graph.invoke(None, config=config)
```
Importantly, LangGraph knows whether a particular step has been executed previously. If it has, LangGraph simply *re-plays* that particular step in the graph and does not re-execute the step, but only for the steps _before_ the provided `checkpoint_id`. All of the steps _after_ `checkpoint_id` will be executed (i.e., a new fork), even if they have been executed previously. See this [how to guide on time-travel to learn more about replaying](../how-tos/human_in_the_loop/time-travel.md).
Importantly, LangGraph knows whether a particular step has been executed previously. If it has, LangGraph simply *re-plays* that particular step in the graph and does not re-execute the step, but only for the steps _before_ the provided `checkpoint_id`. All of the steps _after_ `checkpoint_id` will be executed (i.e., a new fork), even if they have been executed previously. See this [how to guide on time-travel to learn more about replaying](../how-tos/human_in_the_loop/time-travel.ipynb).
![Replay](img/persistence/re_play.png)
@@ -224,7 +224,7 @@ The `foo` key (channel) is completely changed (because there is no reducer speci
#### `as_node`
The final thing you can optionally specify when calling `update_state` is `as_node`. If you provided it, the update will be applied as if it came from node `as_node`. If `as_node` is not provided, it will be set to the last node that updated the state, if not ambiguous. The reason this matters is that the next steps to execute depend on the last node to have given an update, so this can be used to control which node executes next. See this [how to guide on time-travel to learn more about forking state](../how-tos/human_in_the_loop/time-travel.md).
The final thing you can optionally specify when calling `update_state` is `as_node`. If you provided it, the update will be applied as if it came from node `as_node`. If `as_node` is not provided, it will be set to the last node that updated the state, if not ambiguous. The reason this matters is that the next steps to execute depend on the last node to have given an update, so this can be used to control which node executes next. See this [how to guide on time-travel to learn more about forking state](../how-tos/human_in_the_loop/time-travel.ipynb).
![Update](img/persistence/checkpoints_full_story.jpg)
@@ -487,12 +487,12 @@ If you want to fallback to pickle for objects not currently supported by our msg
you can use the `pickle_fallback` argument of the `JsonPlusSerializer`:
```python
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.checkpoint.memory import MemorySaver
from langgraph.checkpoint.serde.jsonplus import JsonPlusSerializer
# ... Define the graph ...
graph.compile(
checkpointer=InMemorySaver(serde=JsonPlusSerializer(pickle_fallback=True))
checkpointer=MemorySaver(serde=JsonPlusSerializer(pickle_fallback=True))
)
```
@@ -525,11 +525,11 @@ When running on LangGraph Platform, encryption is automatically enabled whenever
### Human-in-the-loop
First, checkpointers facilitate [human-in-the-loop workflows](agentic_concepts.md#human-in-the-loop) workflows by allowing humans to inspect, interrupt, and approve graph steps. Checkpointers are needed for these workflows as the human has to be able to view the state of a graph at any point in time, and the graph has to be to resume execution after the human has made any updates to the state. See [the how-to guides](../how-tos/human_in_the_loop/add-human-in-the-loop.md) for examples.
First, checkpointers facilitate [human-in-the-loop workflows](agentic_concepts.md#human-in-the-loop) workflows by allowing humans to inspect, interrupt, and approve graph steps. Checkpointers are needed for these workflows as the human has to be able to view the state of a graph at any point in time, and the graph has to be to resume execution after the human has made any updates to the state. See [these how-to guides](../how-tos/human_in_the_loop/breakpoints.ipynb) for concrete examples.
### Memory
Second, checkpointers allow for ["memory"](../concepts/memory.md) between interactions. In the case of repeated human interactions (like conversations) any follow up messages can be sent to that thread, which will retain its memory of previous ones. See [Add memory](../how-tos/memory/add-memory.md) for information on how to add and manage conversation memory using checkpointers.
Second, checkpointers allow for ["memory"](agentic_concepts.md#memory) between interactions. In the case of repeated human interactions (like conversations) any follow up messages can be sent to that thread, which will retain its memory of previous ones. See [this how-to guide](../how-tos/memory.ipynb) for an end-to-end example on how to add and manage conversation memory using checkpointers.
### Time Travel
+1 -1
View File
@@ -20,7 +20,7 @@ There are three different plans for using it.
| | Developer | Plus | Enterprise |
|------------------------------------------------------------------|---------------------------------------------|-------------------------------------------------------|-----------------------------------------------------|
| Deployment Options | Standalone Container (Lite) | Cloud SaaS | <ul><li>Cloud SaaS</li><li>Self-Hosted Data Plane</li><li>Self-Hosted Control Plane</li><li>Standalone Container (Enterprise)</li></ul> |
| Usage | Free, limited to 1M [nodes executed](../concepts/faq.md#what-does-nodes-executed-mean-for-langgraph-platform-usage) per year | See [Pricing](https://www.langchain.com/langgraph-platform-pricing) | Custom |
| Usage | Free, limited to 1M nodes executed per year | Free while in Beta, will be charged per node executed | Custom |
| APIs for retrieving and updating state and conversational history | ✅ | ✅ | ✅ |
| APIs for retrieving and updating long-term memory | ✅ | ✅ | ✅ |
| Horizontally scalable task queues and servers | ✅ | ✅ | ✅ |
+85 -113
View File
@@ -6,13 +6,20 @@ hide:
- tags
---
# MCP endpoint in LangGraph Server
# MCP Endpoint
The [Model Context Protocol (MCP)](./mcp.md) is an open protocol for describing tools and data sources in a model-agnostic format, enabling LLMs to discover and use them via a structured API.
The **Model Context Protocol (MCP)** is an open protocol for describing tools and data sources in a model-agnostic format, enabling LLMs to discover
and use them via a structured API.
[LangGraph Server](./langgraph_server.md) implements MCP using the [Streamable HTTP transport](https://spec.modelcontextprotocol.io/specification/2025-03-26/basic/transports/#streamable-http). This allows LangGraph **agents** to be exposed as **MCP tools**, making them usable with any MCP-compliant client supporting Streamable HTTP.
The MCP endpoint is available at `/mcp` on [LangGraph Server](./langgraph_server.md).
The MCP endpoint is available at:
```
/mcp
```
on [LangGraph Server](./langgraph_server.md).
## Requirements
@@ -27,6 +34,79 @@ Install them with:
pip install "langgraph-api>=0.2.3" "langgraph-sdk>=0.1.61"
```
## Exposing an agent as MCP tool
When deployed, your agent will appear as a tool in the MCP endpoint
with this configuration:
- **Tool name**: The agent's name.
- **Tool description**: The agent's description.
- **Tool input schema**: The agent's input schema.
### Setting name and description
You can set the name and description of your agent in `langgraph.json`:
```json
{
"graphs": {
"my_agent": {
"path": "./my_agent/agent.py:graph",
"description": "A description of what the agent does"
}
},
"env": ".env"
}
```
After deployment, you can update the name and description using the LangGraph SDK.
### Schema
Define clear, minimal input and output schemas to avoid exposing unnecessary internal complexity to the LLM.
The default [MessagesState](./low_level.md#messagesstate) uses `AnyMessage`, which supports many message types but is too general for direct LLM exposure.
Instead, define **custom agents or workflows** that use explicitly typed input and output structures.
For example, a workflow answering documentation questions might look like this:
```python
from langgraph.graph import StateGraph, START, END
from typing_extensions import TypedDict
# Define input schema
class InputState(TypedDict):
question: str
# Define output schema
class OutputState(TypedDict):
answer: str
# Combine input and output
class OverallState(InputState, OutputState):
pass
# Define the processing node
def answer_node(state: InputState):
# Replace with actual logic and do something useful
return {"answer": "bye", "question": state["question"]}
# Build the graph with explicit schemas
builder = StateGraph(OverallState, input_schema=InputState, output_schema=OutputState)
builder.add_node(answer_node)
builder.add_edge(START, "answer_node")
builder.add_edge("answer_node", END)
graph = builder.compile()
# Run the graph
print(graph.invoke({"question": "hi"}))
```
For more details, see the [low-level concepts guide](https://langchain-ai.github.io/langgraph/concepts/low_level/#state).
## Usage overview
To enable MCP:
@@ -127,114 +207,6 @@ Use an MCP-compliant client to connect to the LangGraph server. The following ex
asyncio.run(main())
```
## Expose an agent as MCP tool
When deployed, your agent will appear as a tool in the MCP endpoint
with this configuration:
- **Tool name**: The agent's name.
- **Tool description**: The agent's description.
- **Tool input schema**: The agent's input schema.
### Setting name and description
You can set the name and description of your agent in `langgraph.json`:
```json
{
"graphs": {
"my_agent": {
"path": "./my_agent/agent.py:graph",
"description": "A description of what the agent does"
}
},
"env": ".env"
}
```
After deployment, you can update the name and description using the LangGraph SDK.
### Schema
Define clear, minimal input and output schemas to avoid exposing unnecessary internal complexity to the LLM.
The default [MessagesState](./low_level.md#messagesstate) uses `AnyMessage`, which supports many message types but is too general for direct LLM exposure.
Instead, define **custom agents or workflows** that use explicitly typed input and output structures.
For example, a workflow answering documentation questions might look like this:
```python
from langgraph.graph import StateGraph, START, END
from typing_extensions import TypedDict
# Define input schema
class InputState(TypedDict):
question: str
# Define output schema
class OutputState(TypedDict):
answer: str
# Combine input and output
class OverallState(InputState, OutputState):
pass
# Define the processing node
def answer_node(state: InputState):
# Replace with actual logic and do something useful
return {"answer": "bye", "question": state["question"]}
# Build the graph with explicit schemas
builder = StateGraph(OverallState, input_schema=InputState, output_schema=OutputState)
builder.add_node(answer_node)
builder.add_edge(START, "answer_node")
builder.add_edge("answer_node", END)
graph = builder.compile()
# Run the graph
print(graph.invoke({"question": "hi"}))
```
For more details, see the [low-level concepts guide](https://langchain-ai.github.io/langgraph/concepts/low_level/#state).
## Use user-scoped MCP tools in your deployment
!!! tip "Prerequisites"
You have added your own [custom auth middleware](https://langchain-ai.github.io/langgraph/how-tos/auth/custom_auth/) that populates the `langgraph_auth_user` object, making it accessible through configurable context for every node in your graph.
To make user-scoped tools available to your LangGraph Platform deployment, start with implementing a snippet like the following:
```python
from langchain_mcp_adapters.client import MultiServerMCPClient
def mcp_tools_node(state, config):
user = config["configurable"].get("langgraph_auth_user")
# e.g., user["github_token"], user["email"], etc.
client = MultiServerMCPClient({
"github": {
"transport": "streamable_http", # (1)
"url": "https://my-github-mcp-server/mcp", # (2)
"headers": {
"Authorization": f"Bearer {user['github_token']}"
}
}
})
tools = await client.get_tools() # (3)
# Your tool-calling logic here
tool_messages = ...
return {"messages": tool_messages}
```
1. MCP only supports adding headers to requests made to `streamable_http` and `sse` `transport` servers.
2. Your MCP server URL.
3. Get available tools from your MCP server.
_This can also be done by [rebuilding your graph at runtime](https://langchain-ai.github.io/langgraph/cloud/deployment/graph_rebuild/) to have a different configuration for a new run_
## Session behavior
@@ -244,7 +216,7 @@ The current LangGraph MCP implementation does not support sessions. Each `/mcp`
The `/mcp` endpoint uses the same authentication as the rest of the LangGraph API. Refer to the [authentication guide](./auth.md) for setup details.
## Disable MCP
## Disabling MCP
To disable the MCP endpoint, set `disable_mcp` to `true` in your `langgraph.json` configuration file:
@@ -256,4 +228,4 @@ To disable the MCP endpoint, set `disable_mcp` to `true` in your `langgraph.json
}
```
This will prevent the server from exposing the `/mcp` endpoint.
This will prevent the server from exposing the `/mcp` endpoint.
+2 -2
View File
@@ -12,7 +12,7 @@ Some reasons for using subgraphs are:
The main question when adding subgraphs is how the parent graph and subgraph communicate, i.e. how they pass the [state](./low_level.md#state) between each other during the graph execution. There are two scenarios:
* parent and subgraph have **shared state keys** in their state [schemas](./low_level.md#state). In this case, you can [include the subgraph as a node in the parent graph](../how-tos/subgraph.md#shared-state-schemas)
* parent and subgraph have **shared state keys** in their state [schemas](./low_level.md#state). In this case, you can [include the subgraph as a node in the parent graph](../how-tos/subgraph.ipynb#shared-state-schemas)
```python
from langgraph.graph import StateGraph, MessagesState, START
@@ -40,7 +40,7 @@ The main question when adding subgraphs is how the parent graph and subgraph com
graph.invoke({"messages": [{"role": "user", "content": "hi!"}]})
```
* parent graph and subgraph have **different schemas** (no shared state keys in their state [schemas](./low_level.md#state)). In this case, you have to [call the subgraph from inside a node in the parent graph](../how-tos/subgraph.md#different-state-schemas): this is useful when the parent graph and the subgraph have different state schemas and you need to transform state before or after calling the subgraph
* parent graph and subgraph have **different schemas** (no shared state keys in their state [schemas](./low_level.md#state)). In this case, you have to [call the subgraph from inside a node in the parent graph](../how-tos/subgraph.ipynb#different-state-schemas): this is useful when the parent graph and the subgraph have different state schemas and you need to transform state before or after calling the subgraph
```python
from typing_extensions import TypedDict, Annotated
+1 -1
View File
@@ -64,7 +64,7 @@ To create a new app from a template, use the `langgraph new` command.
=== "JS"
```bash
npm create langgraph@latest
npx @langchain/langgraph-cli new
```
## Next Steps

Some files were not shown because too many files have changed in this diff Show More