Compare commits

..
Author SHA1 Message Date
Vadym BardaandGitHub 048eff9f11 prebuilt: release 0.1.3 (#3830) 2025-03-13 11:46:58 -04:00
ccurmeandGitHub 8a2765c8f2 prebuilt: update type annotation for tools (#3829) 2025-03-13 15:45:44 +00:00
David DuongandGitHub 108a041fa7 feat(sdk-js): add docs for generative UI (#3774) 2025-03-13 15:17:54 +01:00
Tat Dat Duong 52e3c59f07 Replace with jpg 2025-03-13 15:09:24 +01:00
David DuongandGitHub 0e17988332 feat(sdk-js): add overridable ui namespacing (#3809) 2025-03-13 15:02:07 +01:00
Tat Dat Duong 5f0d05099d Bump to 0.0.54 2025-03-13 14:50:59 +01:00
Tat Dat Duong a1739d3184 Add a separate section for Frontend and Generative UI 2025-03-13 14:47:49 +01:00
Tat Dat Duong ab38cc2cc0 Further cleanup 2025-03-13 14:36:07 +01:00
Tat Dat Duong 647833dcaa Separate segments 2025-03-13 14:34:23 +01:00
Tat Dat Duong 1f03735b7d Add image 2025-03-13 14:29:35 +01:00
Vadym BardaandGitHub d980cca59b docs: fix link checking (#3826) 2025-03-13 13:28:35 +00:00
William FHandGitHub 944b93bf61 docs: more concise readme (#3815) 2025-03-13 09:03:18 -04:00
Vadym BardaandGitHub 8aa59d002a docs: add logo to readme (#3816) 2025-03-13 09:03:01 -04:00
Tat Dat Duong ed533b32a8 Add example for CSS 2025-03-13 13:47:20 +01:00
Nuno CamposandGitHub fc5dde6c55 Rename env var (#3813) 2025-03-12 17:07:52 -07:00
Nuno Campos 4c902d21a3 Rename env var 2025-03-12 16:58:12 -07:00
Nuno CamposandGitHub 54804af06a Make default recursion_limit configurable by env var (#3812) 2025-03-12 16:54:59 -07:00
Nuno Campos 6973b19cc7 Make default recursion_limit configurable by env var 2025-03-12 16:45:45 -07:00
Tat Dat Duong 45ed67856f feat(sdk-js): add overridable ui namespacing 2025-03-12 23:56:07 +01:00
Vadym BardaandGitHub 74b2dbe1ea docs: add reflection prebuilt (#3805) 2025-03-12 17:54:59 +00:00
Alexey BondarenkoandGitHub 7f803df586 Add state schemas to __all__ in chat_agent_executor.py (#3798) 2025-03-12 17:54:18 +00:00
Vadym BardaandGitHub a5b43c933a docs: update README (#3799) 2025-03-12 13:43:28 -04:00
Vadym BardaandGitHub aae2fb4b85 langgraph: release 0.3.8 (#3803) 2025-03-12 13:29:21 -04:00
Vadym BardaandGitHub c20a50875d langgraph: handle pydantic state updates better for fields w/ defaults (#3783) 2025-03-12 13:19:56 -04:00
MathieuandGitHub 779553f4aa docs: fix state type in Persistence documentation (#3801)
This PR fixes the type of `foo` in the `State` class in Persistence
documentation. The type was previously defined as `int`, but the code
uses it as a `str`.

Updated the type of `foo` in the documentation to `str` to match its
actual usage in the code.

No changes to the functionality or codebase, only a documentation fix.
2025-03-12 17:14:07 +00:00
ArrayPDandGitHub 537e69608e docs: Correct a typo in create-react-agent-memory.ipynb (#3800)
Fixed a typo in create-react-agent-memory.ipynb
2025-03-12 15:17:11 +00:00
Tat Dat Duong 78348d2d9f Improve docs 2025-03-11 21:06:02 +01:00
Tat Dat Duong 44af8d5257 Add a disclaimer 2025-03-11 19:24:11 +01:00
Tat Dat Duong ed69f60f24 Add missing links 2025-03-11 16:18:59 +01:00
Tat Dat Duong c55f1f12bf Update docs 2025-03-11 16:18:58 +01:00
Tat Dat Duong 5d76b1d624 Add docs 2025-03-11 16:18:58 +01:00
19 changed files with 498 additions and 626 deletions
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@@ -127,6 +127,7 @@ jobs:
--check-links-ignore "https://openai\.com/.*" \
--check-links-ignore "https://www\.uber\.com/.*" \
--check-links-ignore "https://pepy\.tech/.*" \
--check-links-ignore "docs/docs/static/wordmark_*" \
--check-links $(find site -name "index.html" | grep -v 'storm/index.html')
else
@@ -147,6 +148,7 @@ jobs:
--check-links-ignore "https://twitter.com/.*" \
--check-links-ignore "https://github\.com/.*" \
--check-links-ignore "/.*\.(ipynb|html)$" \
--check-links-ignore "docs/docs/static/wordmark_*" \
--check-links ${CHANGED_FILES} \
|| ([ $? = 5 ] && exit 0 || exit $?)
else
+46 -298
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@@ -1,339 +1,87 @@
# 🦜🕸️LangGraph
<picture class="github-only">
<source media="(prefers-color-scheme: light)" srcset="docs/docs/static/wordmark_dark.svg">
<source media="(prefers-color-scheme: dark)" srcset="docs/docs/static/wordmark_light.svg">
<img alt="LangGraph Logo" src="docs/docs/static/wordmark_dark.svg" width="80%">
</picture>
<div>
<br>
</div>
[![Version](https://img.shields.io/pypi/v/langgraph.svg)](https://pypi.org/project/langgraph/)
[![Downloads](https://static.pepy.tech/badge/langgraph/month)](https://pepy.tech/project/langgraph)
[![Open Issues](https://img.shields.io/github/issues-raw/langchain-ai/langgraph)](https://github.com/langchain-ai/langgraph/issues)
[![Docs](https://img.shields.io/badge/docs-latest-blue)](https://langchain-ai.github.io/langgraph/)
⚡ Building language agents as graphs ⚡
> [!NOTE]
> Looking for the JS version? See the [JS repo](https://github.com/langchain-ai/langgraphjs) and the [JS docs](https://langchain-ai.github.io/langgraphjs/).
## Overview
LangGraph — used by Replit, Uber, LinkedIn, GitLab and more — is a low-level orchestration framework for building controllable agents. While langchain provides integrations and composable components to streamline LLM application development, the LangGraph library enables agent orchestration — offering customizable architectures, long-term memory, and human-in-the-loop to reliably handle complex tasks.
[LangGraph](https://langchain-ai.github.io/langgraph/) is a library for building
stateful, multi-actor applications with LLMs, used to create agent and multi-agent
workflows. Check out an introductory tutorial [here](https://langchain-ai.github.io/langgraph/tutorials/introduction/).
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.
### Why use LangGraph?
LangGraph powers [production-grade agents](https://www.langchain.com/built-with-langgraph), trusted by Linkedin, Uber, Klarna, GitLab, and many more. LangGraph provides fine-grained control over both the flow and state of your agent applications. It implements a central [persistence layer](https://langchain-ai.github.io/langgraph/concepts/persistence/), enabling features that are common to most agent architectures:
- **Memory**: LangGraph persists arbitrary aspects of your application's state,
supporting memory of conversations and other updates within and across user
interactions;
- **Human-in-the-loop**: Because state is checkpointed, execution can be interrupted
and resumed, allowing for decisions, validation, and corrections at key stages via
human input.
Standardizing these components allows individuals and teams to focus on the behavior
of their agent, instead of its supporting infrastructure.
Through [LangGraph Platform](#langgraph-platform), LangGraph also provides tooling for
the development, deployment, debugging, and monitoring of your applications.
LangGraph integrates seamlessly with
[LangChain](https://python.langchain.com/docs/introduction/) and
[LangSmith](https://docs.smith.langchain.com/) (but does not require them).
To learn more about LangGraph, check out our first LangChain Academy
course, *Introduction to LangGraph*, available for free
[here](https://academy.langchain.com/courses/intro-to-langgraph).
### LangGraph Platform
[LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform) is infrastructure for deploying LangGraph agents. It is a commercial solution for deploying agentic applications to production, built on the open-source LangGraph framework. The LangGraph Platform consists of several components that work together to support the development, deployment, debugging, and monitoring of LangGraph applications: [LangGraph Server](https://langchain-ai.github.io/langgraph/concepts/langgraph_server) (APIs), [LangGraph SDKs](https://langchain-ai.github.io/langgraph/concepts/sdk) (clients for the APIs), [LangGraph CLI](https://langchain-ai.github.io/langgraph/concepts/langgraph_cli) (command line tool for building the server), and [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio) (UI/debugger).
See deployment options [here](https://langchain-ai.github.io/langgraph/concepts/deployment_options/)
(includes a free tier).
Here are some common issues that arise in complex deployments, which LangGraph Platform addresses:
- **Streaming support**: LangGraph Server provides [multiple streaming modes](https://langchain-ai.github.io/langgraph/concepts/streaming) optimized for various application needs
- **Background runs**: Runs agents asynchronously in the background
- **Support for long running agents**: Infrastructure that can handle long running processes
- **[Double texting](https://langchain-ai.github.io/langgraph/concepts/double_texting)**: Handle the case where you get two messages from the user before the agent can respond
- **Handle burstiness**: Task queue for ensuring requests are handled consistently without loss, even under heavy loads
## Installation
```shell
```bash
pip install -U langgraph
```
## Example
Let's build a tool-calling [ReAct-style](https://langchain-ai.github.io/langgraph/concepts/agentic_concepts/#react-implementation) agent that uses a search tool!
```shell
pip install langchain-anthropic
```
```shell
export ANTHROPIC_API_KEY=sk-...
```
Optionally, we can set up [LangSmith](https://docs.smith.langchain.com/) for best-in-class observability.
```shell
export LANGSMITH_TRACING=true
export LANGSMITH_API_KEY=lsv2_sk_...
```
The simplest way to create a tool-calling agent in LangGraph is to use `create_react_agent`:
<details open>
<summary>High-level implementation</summary>
To learn more about how to use LangGraph, check out [the docs](https://langchain-ai.github.io/langgraph/). We show a simple example below of how to create a ReAct agent.
```python
# This code depends on pip install langchain[anthropic]
from langgraph.prebuilt import create_react_agent
from langgraph.checkpoint.memory import MemorySaver
from langchain_anthropic import ChatAnthropic
from langchain_core.tools import tool
# Define the tools for the agent to use
@tool
def search(query: str):
"""Call to surf the web."""
# This is a placeholder, but don't tell the LLM that...
if "sf" in query.lower() or "san francisco" in query.lower():
return "It's 60 degrees and foggy."
return "It's 90 degrees and sunny."
tools = [search]
model = ChatAnthropic(model="claude-3-5-sonnet-latest", temperature=0)
# Initialize memory to persist state between graph runs
checkpointer = MemorySaver()
app = create_react_agent(model, tools, checkpointer=checkpointer)
# Use the agent
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
config={"configurable": {"thread_id": 42}}
agent = create_react_agent("anthropic:claude-3-7-sonnet-latest", tools=[search])
agent.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]}
)
final_state["messages"][-1].content
```
```
"Based on the search results, I can tell you that the current weather in San Francisco is:\n\nTemperature: 60 degrees Fahrenheit\nConditions: Foggy\n\nSan Francisco is known for its microclimates and frequent fog, especially during the summer months. The temperature of 60°F (about 15.5°C) is quite typical for the city, which tends to have mild temperatures year-round. The fog, often referred to as "Karl the Fog" by locals, is a characteristic feature of San Francisco\'s weather, particularly in the mornings and evenings.\n\nIs there anything else you\'d like to know about the weather in San Francisco or any other location?"
```
Now when we pass the same <code>"thread_id"</code>, the conversation context is retained via the saved state (i.e. stored list of messages)
## Why use LangGraph?
```python
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what about ny"}]},
config={"configurable": {"thread_id": 42}}
)
final_state["messages"][-1].content
```
LangGraph is built for developers who want to build powerful, adaptable AI agents. Developers choose LangGraph for:
```
"Based on the search results, I can tell you that the current weather in New York City is:\n\nTemperature: 90 degrees Fahrenheit (approximately 32.2 degrees Celsius)\nConditions: Sunny\n\nThis weather is quite different from what we just saw in San Francisco. New York is experiencing much warmer temperatures right now. Here are a few points to note:\n\n1. The temperature of 90°F is quite hot, typical of summer weather in New York City.\n2. The sunny conditions suggest clear skies, which is great for outdoor activities but also means it might feel even hotter due to direct sunlight.\n3. This kind of weather in New York often comes with high humidity, which can make it feel even warmer than the actual temperature suggests.\n\nIt's interesting to see the stark contrast between San Francisco's mild, foggy weather and New York's hot, sunny conditions. This difference illustrates how varied weather can be across different parts of the United States, even on the same day.\n\nIs there anything else you'd like to know about the weather in New York or any other location?"
```
</details>
- **Reliability and controllability.** Steer agent actions with moderation checks and human-in-the-loop approvals. LangGraph persists context for long-running workflows, keeping your agents on course.
- **Low-level and extensible.** Build custom agents with fully descriptive, low-level primitives free from rigid abstractions that limit customization. Design scalable multi-agent systems, with each agent serving a specific role tailored to your use case.
- **First-class streaming support.** With token-by-token streaming and streaming of intermediate steps, LangGraph gives users clear visibility into agent reasoning and actions as they unfold in real time.
> [!TIP]
> LangGraph is a **low-level** framework that allows you to implement any custom agent
architectures. Click on the low-level implementation below to see how to implement a
tool-calling agent from scratch.
LangGraph is trusted in production and powering agents for companies like:
<details>
<summary>Low-level implementation</summary>
- [Klarna](https://blog.langchain.dev/customers-klarna/): Customer support bot for 85 million active users
- [Elastic](https://www.elastic.co/blog/elastic-security-generative-ai-features): Security AI assistant for threat detection
- [Uber](https://dpe.org/sessions/ty-smith-adam-huda/this-year-in-ubers-ai-driven-developer-productivity-revolution/): Automated unit test generation
- [Replit](https://www.langchain.com/breakoutagents/replit): Code generation
- And many more ([see list here](https://www.langchain.com/built-with-langgraph))
```python
from typing import Literal
## LangGraphs ecosystem
from langchain_anthropic import ChatAnthropic
from langchain_core.tools import tool
from langgraph.checkpoint.memory import MemorySaver
from langgraph.graph import END, START, StateGraph, MessagesState
from langgraph.prebuilt import ToolNode
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/).
# Define the tools for the agent to use
@tool
def search(query: str):
"""Call to surf the web."""
# This is a placeholder, but don't tell the LLM that...
if "sf" in query.lower() or "san francisco" in query.lower():
return "It's 60 degrees and foggy."
return "It's 90 degrees and sunny."
## Pairing with LangGraph Platform
While LangGraph is our open-source agent orchestration framework, enterprises that need scalable agent deployment can benefit from [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform/).
tools = [search]
LangGraph Platform can help engineering teams:
tool_node = ToolNode(tools)
- **Accelerate agent development**: Quickly create agent UXs with configurable templates and [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio/) for visualizing and debugging agent interactions.
- **Deploy seamlessly**: We handle the complexity of deploying your agent. LangGraph Platform includes robust APIs for memory, threads, and cron jobs plus auto-scaling task queues & servers.
- **Centralize agent management & reusability**: Discover, reuse, and manage agents across the organization. Business users can also modify agents without coding.
model = ChatAnthropic(model="claude-3-5-sonnet-latest", temperature=0).bind_tools(tools)
## Additional resources
# Define the function that determines whether to continue or not
def should_continue(state: MessagesState) -> Literal["tools", END]:
messages = state['messages']
last_message = messages[-1]
# If the LLM makes a tool call, then we route to the "tools" node
if last_message.tool_calls:
return "tools"
# Otherwise, we stop (reply to the user)
return END
- [LangChain Academy](https://academy.langchain.com/courses/intro-to-langgraph): Learn the basics of LangGraph in our free, structured course.
- [Tutorials](https://langchain-ai.github.io/langgraph/tutorials/): Simple walkthroughs with guided examples on getting started with LangGraph.
- [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.
- [How-to 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.).
- [API 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.
- [Built with LangGraph](https://www.langchain.com/built-with-langgraph): Hear how industry leaders use LangGraph to ship powerful, production-ready AI applications.
## Acknowledgements
# Define the function that calls the model
def call_model(state: MessagesState):
messages = state['messages']
response = model.invoke(messages)
# We return a list, because this will get added to the existing list
return {"messages": [response]}
# Define a new graph
workflow = StateGraph(MessagesState)
# Define the two nodes we will cycle between
workflow.add_node("agent", call_model)
workflow.add_node("tools", tool_node)
# Set the entrypoint as `agent`
# This means that this node is the first one called
workflow.add_edge(START, "agent")
# We now add a conditional edge
workflow.add_conditional_edges(
# First, we define the start node. We use `agent`.
# This means these are the edges taken after the `agent` node is called.
"agent",
# Next, we pass in the function that will determine which node is called next.
should_continue,
)
# We now add a normal edge from `tools` to `agent`.
# This means that after `tools` is called, `agent` node is called next.
workflow.add_edge("tools", 'agent')
# Initialize memory to persist state between graph runs
checkpointer = MemorySaver()
# Finally, we compile it!
# This compiles it into a LangChain Runnable,
# meaning you can use it as you would any other runnable.
# Note that we're (optionally) passing the memory when compiling the graph
app = workflow.compile(checkpointer=checkpointer)
# Use the agent
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
config={"configurable": {"thread_id": 42}}
)
final_state["messages"][-1].content
```
<b>Step-by-step Breakdown</b>:
<details>
<summary>Initialize the model and tools.</summary>
<ul>
<li>
We use <code>ChatAnthropic</code> as our LLM. <strong>NOTE:</strong> we need to make sure the model knows that it has these tools available to call. We can do this by converting the LangChain tools into the format for OpenAI tool calling using the <code>.bind_tools()</code> method.
</li>
<li>
We define the tools we want to use - a search tool in our case. It is really easy to create your own tools - see documentation here on how to do that <a href="https://python.langchain.com/docs/how_to/custom_tools/">here</a>.
</li>
</ul>
</details>
<details>
<summary>Initialize graph with state.</summary>
<ul>
<li>We initialize graph (<code>StateGraph</code>) by passing state schema (in our case <code>MessagesState</code>)</li>
<li><code>MessagesState</code> is a prebuilt state schema that has one attribute -- a list of LangChain <code>Message</code> objects, as well as logic for merging the updates from each node into the state.</li>
</ul>
</details>
<details>
<summary>Define graph nodes.</summary>
There are two main nodes we need:
<ul>
<li>The <code>agent</code> node: responsible for deciding what (if any) actions to take.</li>
<li>The <code>tools</code> node that invokes tools: if the agent decides to take an action, this node will then execute that action.</li>
</ul>
</details>
<details>
<summary>Define entry point and graph edges.</summary>
First, we need to set the entry point for graph execution - <code>agent</code> node.
Then we define one normal and one conditional edge. Conditional edge means that the destination depends on the contents of the graph's state (<code>MessagesState</code>). In our case, the destination is not known until the agent (LLM) decides.
<ul>
<li>Conditional edge: after the agent is called, we should either:
<ul>
<li>a. Run tools if the agent said to take an action, OR</li>
<li>b. Finish (respond to the user) if the agent did not ask to run tools</li>
</ul>
</li>
<li>Normal edge: after the tools are invoked, the graph should always return to the agent to decide what to do next</li>
</ul>
</details>
<details>
<summary>Compile the graph.</summary>
<ul>
<li>
When we compile the graph, we turn it into a LangChain
<a href="https://python.langchain.com/docs/concepts/runnables/">Runnable</a>,
which automatically enables calling <code>.invoke()</code>, <code>.stream()</code> and <code>.batch()</code>
with your inputs
</li>
<li>
We can also optionally pass checkpointer object for persisting state between graph runs, and enabling memory,
human-in-the-loop workflows, time travel and more. In our case we use <code>MemorySaver</code> -
a simple in-memory checkpointer
</li>
</ul>
</details>
<details>
<summary>Execute the graph.</summary>
<ol>
<li>LangGraph adds the input message to the internal state, then passes the state to the entrypoint node, <code>"agent"</code>.</li>
<li>The <code>"agent"</code> node executes, invoking the chat model.</li>
<li>The chat model returns an <code>AIMessage</code>. LangGraph adds this to the state.</li>
<li>Graph cycles the following steps until there are no more <code>tool_calls</code> on <code>AIMessage</code>:
<ul>
<li>If <code>AIMessage</code> has <code>tool_calls</code>, <code>"tools"</code> node executes</li>
<li>The <code>"agent"</code> node executes again and returns <code>AIMessage</code></li>
</ul>
</li>
<li>Execution progresses to the special <code>END</code> value and outputs the final state. And as a result, we get a list of all our chat messages as output.</li>
</ol>
</details>
</details>
## Documentation
* [Tutorials](https://langchain-ai.github.io/langgraph/tutorials/): Learn to build with LangGraph through guided examples.
* [How-to Guides](https://langchain-ai.github.io/langgraph/how-tos/): Accomplish specific things within LangGraph, from streaming, to adding memory & persistence, to common design patterns (branching, subgraphs, etc.), these are the place to go if you want to copy and run a specific code snippet.
* [Conceptual Guides](https://langchain-ai.github.io/langgraph/concepts/high_level/): In-depth explanations of the key concepts and principles behind LangGraph, such as nodes, edges, state and more.
* [API Reference](https://langchain-ai.github.io/langgraph/reference/graphs/): Review important classes and methods, simple examples of how to use the graph and checkpointing APIs, higher-level prebuilt components and more.
* [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/#langgraph-platform): LangGraph Platform is a commercial solution for deploying agentic applications in production, built on the open-source LangGraph framework.
## Resources
* [Built with LangGraph](https://www.langchain.com/built-with-langgraph): Hear how industry leaders use LangGraph to ship powerful, production-ready AI applications.
## Contributing
For more information on how to contribute, see [here](https://github.com/langchain-ai/langgraph/blob/main/CONTRIBUTING.md).
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.
@@ -30,3 +30,6 @@ packages:
- name: "langgraph-bigtool"
repo: "langchain-ai/langgraph-bigtool"
description: "Build LangGraph agents with large numbers of tools."
- name: "langgraph-reflection"
repo: "langchain-ai/langgraph-reflection"
description: "LangGraph agent that runs a reflection step."
@@ -0,0 +1,305 @@
# How to implement Generative User Interfaces with LangGraph
!!! info "Prerequisites"
- [LangGraph Platform](../../concepts/langgraph_platform.md)
- [LangGraph Server](../../concepts/langgraph_server.md)
- [`useStream()` React Hook](./use_stream_react.md)
Generative user interfaces (Generative UI) allows agents to go beyond text and generate rich user interfaces. This enables creating more interactive and context-aware applications where the UI adapts based on the conversation flow and AI responses.
![Generative UI Sample](./img/generative_ui_sample.jpg)
LangGraph Platform supports colocating your React components with your graph code. This allows you to focus on building specific UI components for your graph while easily plugging into existing chat interfaces such as [Agent Chat](https://agentchat.vercel.app) and loading the code only when actually needed.
!!! warning "LangGraph.js only"
Currently only LangGraph.js supports Generative UI. Support for Python is coming soon.
## Tutorial
### 1. Define and configure UI components
First, create your first UI component. For each component you need to provide an unique identifier that will be used to reference the component in your graph code.
```tsx title="src/agent/ui.tsx"
const WeatherComponent = (props: { city: string }) => {
return <div>Weather for {props.city}</div>;
};
export default {
weather: WeatherComponent,
};
```
Next, define your UI components in your `langgraph.json` configuration:
```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.
LangGraph Platform will automatically bundle your UI components code and styles and serve them as external assets that can be loaded by the `LoadExternalComponent` component. Some dependencies such as `react` and `react-dom` will be automatically excluded from the bundle.
CSS and Tailwind 4.x is also supported out of the box, so you can freely use Tailwind classes as well as `shadcn/ui` in your UI components.
=== "`src/agent/ui.tsx`"
```tsx
import "./styles.css";
const WeatherComponent = (props: { city: string }) => {
return <div className="bg-red-500">Weather for {props.city}</div>;
};
export default {
weather: WeatherComponent,
};
```
=== "`src/agent/styles.css`"
```css
@import "tailwindcss";
```
### 2. Send the UI components in your graph
Use the `typedUi` utility to emit UI elements from your agent nodes:
```typescript title="src/agent/index.ts"
import {
typedUi,
uiMessageReducer,
} from "@langchain/langgraph-sdk/react-ui/server";
import { ChatOpenAI } from "@langchain/openai";
import { v4 as uuidv4 } from "uuid";
import { z } from "zod";
import type ComponentMap from "./ui.js";
import {
Annotation,
MessagesAnnotation,
StateGraph,
type LangGraphRunnableConfig,
} from "@langchain/langgraph";
const AgentState = Annotation.Root({
...MessagesAnnotation.spec,
ui: Annotation({ reducer: uiMessageReducer, default: () => [] }),
});
export const graph = new StateGraph(AgentState)
.addNode("weather", async (state, config) => {
// Provide the type of the component map to ensure
// type safety of `ui.push()` calls.
const ui = typedUi<typeof ComponentMap>(config);
const weather = await new ChatOpenAI({ model: "gpt-4o-mini" })
.withStructuredOutput(z.object({ city: z.string() }))
.withConfig({ tags: ["langsmith:nostream"] })
.invoke(state.messages);
const response = {
id: uuidv4(),
type: "ai",
content: `Here's the weather for ${weather.city}`,
};
// Emit UI elements with associated AI message
ui.push({ name: "weather", props: weather }, { message: response });
return { messages: [response], ui: ui.items };
})
.addEdge("__start__", "weather")
.compile();
```
### 3. Handle UI elements in your React application
On the client side, you can use `useStream()` and `LoadExternalComponent` to display the UI elements.
```tsx title="src/app/page.tsx"
"use client";
import { useStream } from "@langchain/langgraph-sdk/react";
import { LoadExternalComponent } from "@langchain/langgraph-sdk/react-ui";
export default function Page() {
const { thread, values } = useStream({
apiUrl: "http://localhost:2024",
assistantId: "agent",
});
return (
<div>
{thread.messages.map((message) => (
<div key={message.id}>
{message.content}
{values.ui
?.filter((ui) => ui.metadata?.message_id === message.id)
.map((ui) => (
<LoadExternalComponent key={ui.id} stream={thread} message={ui} />
))}
</div>
))}
</div>
);
}
```
Behind the scenes, `LoadExternalComponent` will fetch the JS and CSS for the UI components from LangGraph Platform and render them in a shadow DOM, thus ensuring style isolation from the rest of your application.
## How-to guides
### Show loading UI when components are loading
You can provide a fallback UI to be rendered when the components are loading.
```tsx
<LoadExternalComponent
stream={thread}
message={ui}
fallback={<div>Loading...</div>}
/>
```
### Provide custom components on the client side
If you already have the components loaded in your client application, you can provide a map of such components to be rendered directly without fetching the UI code from LangGraph Platform.
```tsx
const clientComponents = {
weather: WeatherComponent,
};
<LoadExternalComponent
stream={thread}
message={ui}
components={clientComponents}
/>;
```
### Customise the namespace of UI components.
By default `LoadExternalComponent` will use the `assistantId` from `useStream()` hook to fetch the code for UI components. You can customise this by providing a `namespace` prop to the `LoadExternalComponent` component.
=== "`src/app/page.tsx`"
```tsx
<LoadExternalComponent
stream={thread}
message={ui}
namespace="custom-namespace"
/>
```
=== "`langgraph.json`"
```json
{
"ui": {
"custom-namespace": "./src/agent/ui.tsx"
}
}
```
### Access and interact with the thread state from the UI component
You can access the thread state from the UI component by using the `useStreamContext` hook.
```tsx
import { useStreamContext } from "@langchain/langgraph-sdk/react-ui";
const WeatherComponent = (props: { city: string }) => {
const { thread, submit } = useStreamContext();
return (
<>
<div>Weather for {props.city}</div>
<button
onClick={() => {
const newMessage = {
type: "human",
content: `What's the weather in ${props.city}?`,
};
submit({ messages: [newMessage] });
}}
>
Retry
</button>
</>
);
};
```
### Pass additional context to the client components
You can pass additional context to the client components by providing a `meta` prop to the `LoadExternalComponent` component.
```tsx
<LoadExternalComponent stream={thread} message={ui} meta={{ userId: "123" }} />
```
Then, you can access the `meta` prop in the UI component by using the `useStreamContext` hook.
```tsx
const WeatherComponent = (props: { city: string }) => {
const { meta } = useStreamContext();
return (
<div>
Weather for {props.city} (user: {meta?.userId})
</div>
);
};
```
### Streaming UI updates before the node execution is finished
You can stream UI updates before the node execution is finished by using the `onCustomEvent` callback of the `useStream()` hook.
```tsx
import { uiMessageReducer } from "@langchain/langgraph-sdk/react-ui";
const { thread, submit } = useStream({
apiUrl: "http://localhost:2024",
assistantId: "agent",
onCustomEvent: (event, options) => {
options.mutate((prev) => {
const ui = uiMessageReducer(prev.ui ?? [], event);
return { ...prev, ui };
});
},
});
```
### Remove UI messages from state
Similar to how messages can be removed from the state by appending a RemoveMessage you can remove an UI message from the state by calling `ui.delete` with the ID of the UI message.
```tsx
// pushed message
const message = ui.push({ name: "weather", props: { city: "London" } });
// remove said message
ui.delete(message.id);
// return new state to persist changes
return { ui: ui.items };
```
## Learn more
- [JS/TS SDK Reference](../reference/sdk/js_ts_sdk_ref.md)
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@@ -32,7 +32,7 @@ from typing_extensions import TypedDict
from operator import add
class State(TypedDict):
foo: int
foo: str
bar: Annotated[list[str], add]
def node_a(state: State):
@@ -220,7 +220,7 @@
"id": "838a043f-90ad-4e69-9d1d-6e22db2c346c",
"metadata": {},
"source": [
"Notice that when we pass the same the same thread ID, the chat history is preserved"
"Notice that when we pass the same thread ID, the chat history is preserved."
]
},
{
+7 -1
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@@ -198,7 +198,6 @@ Learn how to set up your app for deployment to LangGraph Platform:
- [How to test locally](../cloud/deployment/test_locally.md)
- [How to rebuild graph at runtime](../cloud/deployment/graph_rebuild.md)
- [How to use LangGraph Platform to deploy CrewAI, AutoGen, and other frameworks](autogen-langgraph-platform.ipynb)
- [How to integrate LangGraph into your React application](../cloud/how-tos/use_stream_react.md)
### Deployment
@@ -257,6 +256,13 @@ Streaming the results of your LLM application is vital for ensuring a good user
- [How to stream in debug mode](../cloud/how-tos/stream_debug.md)
- [How to stream multiple modes](../cloud/how-tos/stream_multiple.md)
### Frontend and Generative UI
With LangGraph Platform you can integrate LangGraph agents into your React applications and colocate UI components with your agent code.
- [How to integrate LangGraph into your React application](../cloud/how-tos/use_stream_react.md)
- [How to implement Generative User Interfaces with LangGraph](../cloud/how-tos/generative_ui_react.md)
### Human-in-the-loop
When designing complex graphs, relying entirely on the LLM for decision-making can be risky, particularly when it involves tools that interact with files, APIs, or databases. These interactions may lead to unintended data access or modifications, depending on the use case. To mitigate these risks, LangGraph allows you to integrate human-in-the-loop behavior, ensuring your LLM applications operate as intended without undesirable outcomes.
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title: Home
---
<script>
// This script only runs in MkDocs, not on GitHub
var hideGitHubVersion = function() {
document.querySelectorAll('.github-only').forEach(el => el.style.display = 'none');
};
// Handle both initial load and subsequent navigation
document.addEventListener('DOMContentLoaded', hideGitHubVersion);
document$.subscribe(hideGitHubVersion);
</script>
<p class="mkdocs-only">
<img class="logo-light" src="static/wordmark_dark.svg" alt="LangGraph Logo" width="80%">
<img class="logo-dark" src="static/wordmark_light.svg" alt="LangGraph Logo" width="80%">
</p>
<style>
h1 {
display: none;
}
</style>
{!../README.md!}
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nav:
- Home:
- Introduction: index.md
- index.md
- Get started:
- Learn the basics: tutorials/introduction.ipynb
- Deployment:
@@ -231,6 +231,7 @@ nav:
- cloud/how-tos/stream_debug.md
- cloud/how-tos/stream_multiple.md
- cloud/how-tos/use_stream_react.md
- cloud/how-tos/generative_ui_react.md
- Human-in-the-loop:
- Human-in-the-loop: how-tos#human-in-the-loop_1
- cloud/how-tos/human_in_the_loop_breakpoint.md
+46 -298
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# 🦜🕸️LangGraph
<picture class="github-only">
<source media="(prefers-color-scheme: light)" srcset="docs/docs/static/wordmark_dark.svg">
<source media="(prefers-color-scheme: dark)" srcset="docs/docs/static/wordmark_light.svg">
<img alt="LangGraph Logo" src="docs/docs/static/wordmark_dark.svg" width="80%">
</picture>
<div>
<br>
</div>
[![Version](https://img.shields.io/pypi/v/langgraph.svg)](https://pypi.org/project/langgraph/)
[![Downloads](https://static.pepy.tech/badge/langgraph/month)](https://pepy.tech/project/langgraph)
[![Open Issues](https://img.shields.io/github/issues-raw/langchain-ai/langgraph)](https://github.com/langchain-ai/langgraph/issues)
[![Docs](https://img.shields.io/badge/docs-latest-blue)](https://langchain-ai.github.io/langgraph/)
⚡ Building language agents as graphs ⚡
> [!NOTE]
> Looking for the JS version? See the [JS repo](https://github.com/langchain-ai/langgraphjs) and the [JS docs](https://langchain-ai.github.io/langgraphjs/).
## Overview
LangGraph — used by Replit, Uber, LinkedIn, GitLab and more — is a low-level orchestration framework for building controllable agents. While langchain provides integrations and composable components to streamline LLM application development, the LangGraph library enables agent orchestration — offering customizable architectures, long-term memory, and human-in-the-loop to reliably handle complex tasks.
[LangGraph](https://langchain-ai.github.io/langgraph/) is a library for building
stateful, multi-actor applications with LLMs, used to create agent and multi-agent
workflows. Check out an introductory tutorial [here](https://langchain-ai.github.io/langgraph/tutorials/introduction/).
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.
### Why use LangGraph?
LangGraph powers [production-grade agents](https://www.langchain.com/built-with-langgraph), trusted by Linkedin, Uber, Klarna, GitLab, and many more. LangGraph provides fine-grained control over both the flow and state of your agent applications. It implements a central [persistence layer](https://langchain-ai.github.io/langgraph/concepts/persistence/), enabling features that are common to most agent architectures:
- **Memory**: LangGraph persists arbitrary aspects of your application's state,
supporting memory of conversations and other updates within and across user
interactions;
- **Human-in-the-loop**: Because state is checkpointed, execution can be interrupted
and resumed, allowing for decisions, validation, and corrections at key stages via
human input.
Standardizing these components allows individuals and teams to focus on the behavior
of their agent, instead of its supporting infrastructure.
Through [LangGraph Platform](#langgraph-platform), LangGraph also provides tooling for
the development, deployment, debugging, and monitoring of your applications.
LangGraph integrates seamlessly with
[LangChain](https://python.langchain.com/docs/introduction/) and
[LangSmith](https://docs.smith.langchain.com/) (but does not require them).
To learn more about LangGraph, check out our first LangChain Academy
course, *Introduction to LangGraph*, available for free
[here](https://academy.langchain.com/courses/intro-to-langgraph).
### LangGraph Platform
[LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform) is infrastructure for deploying LangGraph agents. It is a commercial solution for deploying agentic applications to production, built on the open-source LangGraph framework. The LangGraph Platform consists of several components that work together to support the development, deployment, debugging, and monitoring of LangGraph applications: [LangGraph Server](https://langchain-ai.github.io/langgraph/concepts/langgraph_server) (APIs), [LangGraph SDKs](https://langchain-ai.github.io/langgraph/concepts/sdk) (clients for the APIs), [LangGraph CLI](https://langchain-ai.github.io/langgraph/concepts/langgraph_cli) (command line tool for building the server), and [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio) (UI/debugger).
See deployment options [here](https://langchain-ai.github.io/langgraph/concepts/deployment_options/)
(includes a free tier).
Here are some common issues that arise in complex deployments, which LangGraph Platform addresses:
- **Streaming support**: LangGraph Server provides [multiple streaming modes](https://langchain-ai.github.io/langgraph/concepts/streaming) optimized for various application needs
- **Background runs**: Runs agents asynchronously in the background
- **Support for long running agents**: Infrastructure that can handle long running processes
- **[Double texting](https://langchain-ai.github.io/langgraph/concepts/double_texting)**: Handle the case where you get two messages from the user before the agent can respond
- **Handle burstiness**: Task queue for ensuring requests are handled consistently without loss, even under heavy loads
## Installation
```shell
```bash
pip install -U langgraph
```
## Example
Let's build a tool-calling [ReAct-style](https://langchain-ai.github.io/langgraph/concepts/agentic_concepts/#react-implementation) agent that uses a search tool!
```shell
pip install langchain-anthropic
```
```shell
export ANTHROPIC_API_KEY=sk-...
```
Optionally, we can set up [LangSmith](https://docs.smith.langchain.com/) for best-in-class observability.
```shell
export LANGSMITH_TRACING=true
export LANGSMITH_API_KEY=lsv2_sk_...
```
The simplest way to create a tool-calling agent in LangGraph is to use `create_react_agent`:
<details open>
<summary>High-level implementation</summary>
To learn more about how to use LangGraph, check out [the docs](https://langchain-ai.github.io/langgraph/). We show a simple example below of how to create a ReAct agent.
```python
# This code depends on pip install langchain[anthropic]
from langgraph.prebuilt import create_react_agent
from langgraph.checkpoint.memory import MemorySaver
from langchain_anthropic import ChatAnthropic
from langchain_core.tools import tool
# Define the tools for the agent to use
@tool
def search(query: str):
"""Call to surf the web."""
# This is a placeholder, but don't tell the LLM that...
if "sf" in query.lower() or "san francisco" in query.lower():
return "It's 60 degrees and foggy."
return "It's 90 degrees and sunny."
tools = [search]
model = ChatAnthropic(model="claude-3-5-sonnet-latest", temperature=0)
# Initialize memory to persist state between graph runs
checkpointer = MemorySaver()
app = create_react_agent(model, tools, checkpointer=checkpointer)
# Use the agent
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
config={"configurable": {"thread_id": 42}}
agent = create_react_agent("anthropic:claude-3-7-sonnet-latest", tools=[search])
agent.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]}
)
final_state["messages"][-1].content
```
```
"Based on the search results, I can tell you that the current weather in San Francisco is:\n\nTemperature: 60 degrees Fahrenheit\nConditions: Foggy\n\nSan Francisco is known for its microclimates and frequent fog, especially during the summer months. The temperature of 60°F (about 15.5°C) is quite typical for the city, which tends to have mild temperatures year-round. The fog, often referred to as "Karl the Fog" by locals, is a characteristic feature of San Francisco\'s weather, particularly in the mornings and evenings.\n\nIs there anything else you\'d like to know about the weather in San Francisco or any other location?"
```
Now when we pass the same <code>"thread_id"</code>, the conversation context is retained via the saved state (i.e. stored list of messages)
## Why use LangGraph?
```python
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what about ny"}]},
config={"configurable": {"thread_id": 42}}
)
final_state["messages"][-1].content
```
LangGraph is built for developers who want to build powerful, adaptable AI agents. Developers choose LangGraph for:
```
"Based on the search results, I can tell you that the current weather in New York City is:\n\nTemperature: 90 degrees Fahrenheit (approximately 32.2 degrees Celsius)\nConditions: Sunny\n\nThis weather is quite different from what we just saw in San Francisco. New York is experiencing much warmer temperatures right now. Here are a few points to note:\n\n1. The temperature of 90°F is quite hot, typical of summer weather in New York City.\n2. The sunny conditions suggest clear skies, which is great for outdoor activities but also means it might feel even hotter due to direct sunlight.\n3. This kind of weather in New York often comes with high humidity, which can make it feel even warmer than the actual temperature suggests.\n\nIt's interesting to see the stark contrast between San Francisco's mild, foggy weather and New York's hot, sunny conditions. This difference illustrates how varied weather can be across different parts of the United States, even on the same day.\n\nIs there anything else you'd like to know about the weather in New York or any other location?"
```
</details>
- **Reliability and controllability.** Steer agent actions with moderation checks and human-in-the-loop approvals. LangGraph persists context for long-running workflows, keeping your agents on course.
- **Low-level and extensible.** Build custom agents with fully descriptive, low-level primitives free from rigid abstractions that limit customization. Design scalable multi-agent systems, with each agent serving a specific role tailored to your use case.
- **First-class streaming support.** With token-by-token streaming and streaming of intermediate steps, LangGraph gives users clear visibility into agent reasoning and actions as they unfold in real time.
> [!TIP]
> LangGraph is a **low-level** framework that allows you to implement any custom agent
architectures. Click on the low-level implementation below to see how to implement a
tool-calling agent from scratch.
LangGraph is trusted in production and powering agents for companies like:
<details>
<summary>Low-level implementation</summary>
- [Klarna](https://blog.langchain.dev/customers-klarna/): Customer support bot for 85 million active users
- [Elastic](https://www.elastic.co/blog/elastic-security-generative-ai-features): Security AI assistant for threat detection
- [Uber](https://dpe.org/sessions/ty-smith-adam-huda/this-year-in-ubers-ai-driven-developer-productivity-revolution/): Automated unit test generation
- [Replit](https://www.langchain.com/breakoutagents/replit): Code generation
- And many more ([see list here](https://www.langchain.com/built-with-langgraph))
```python
from typing import Literal
## LangGraphs ecosystem
from langchain_anthropic import ChatAnthropic
from langchain_core.tools import tool
from langgraph.checkpoint.memory import MemorySaver
from langgraph.graph import END, START, StateGraph, MessagesState
from langgraph.prebuilt import ToolNode
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/).
# Define the tools for the agent to use
@tool
def search(query: str):
"""Call to surf the web."""
# This is a placeholder, but don't tell the LLM that...
if "sf" in query.lower() or "san francisco" in query.lower():
return "It's 60 degrees and foggy."
return "It's 90 degrees and sunny."
## Pairing with LangGraph Platform
While LangGraph is our open-source agent orchestration framework, enterprises that need scalable agent deployment can benefit from [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/langgraph_platform/).
tools = [search]
LangGraph Platform can help engineering teams:
tool_node = ToolNode(tools)
- **Accelerate agent development**: Quickly create agent UXs with configurable templates and [LangGraph Studio](https://langchain-ai.github.io/langgraph/concepts/langgraph_studio/) for visualizing and debugging agent interactions.
- **Deploy seamlessly**: We handle the complexity of deploying your agent. LangGraph Platform includes robust APIs for memory, threads, and cron jobs plus auto-scaling task queues & servers.
- **Centralize agent management & reusability**: Discover, reuse, and manage agents across the organization. Business users can also modify agents without coding.
model = ChatAnthropic(model="claude-3-5-sonnet-latest", temperature=0).bind_tools(tools)
## Additional resources
# Define the function that determines whether to continue or not
def should_continue(state: MessagesState) -> Literal["tools", END]:
messages = state['messages']
last_message = messages[-1]
# If the LLM makes a tool call, then we route to the "tools" node
if last_message.tool_calls:
return "tools"
# Otherwise, we stop (reply to the user)
return END
- [LangChain Academy](https://academy.langchain.com/courses/intro-to-langgraph): Learn the basics of LangGraph in our free, structured course.
- [Tutorials](https://langchain-ai.github.io/langgraph/tutorials/): Simple walkthroughs with guided examples on getting started with LangGraph.
- [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.
- [How-to 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.).
- [API 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.
- [Built with LangGraph](https://www.langchain.com/built-with-langgraph): Hear how industry leaders use LangGraph to ship powerful, production-ready AI applications.
## Acknowledgements
# Define the function that calls the model
def call_model(state: MessagesState):
messages = state['messages']
response = model.invoke(messages)
# We return a list, because this will get added to the existing list
return {"messages": [response]}
# Define a new graph
workflow = StateGraph(MessagesState)
# Define the two nodes we will cycle between
workflow.add_node("agent", call_model)
workflow.add_node("tools", tool_node)
# Set the entrypoint as `agent`
# This means that this node is the first one called
workflow.add_edge(START, "agent")
# We now add a conditional edge
workflow.add_conditional_edges(
# First, we define the start node. We use `agent`.
# This means these are the edges taken after the `agent` node is called.
"agent",
# Next, we pass in the function that will determine which node is called next.
should_continue,
)
# We now add a normal edge from `tools` to `agent`.
# This means that after `tools` is called, `agent` node is called next.
workflow.add_edge("tools", 'agent')
# Initialize memory to persist state between graph runs
checkpointer = MemorySaver()
# Finally, we compile it!
# This compiles it into a LangChain Runnable,
# meaning you can use it as you would any other runnable.
# Note that we're (optionally) passing the memory when compiling the graph
app = workflow.compile(checkpointer=checkpointer)
# Use the agent
final_state = app.invoke(
{"messages": [{"role": "user", "content": "what is the weather in sf"}]},
config={"configurable": {"thread_id": 42}}
)
final_state["messages"][-1].content
```
<b>Step-by-step Breakdown</b>:
<details>
<summary>Initialize the model and tools.</summary>
<ul>
<li>
We use <code>ChatAnthropic</code> as our LLM. <strong>NOTE:</strong> we need to make sure the model knows that it has these tools available to call. We can do this by converting the LangChain tools into the format for OpenAI tool calling using the <code>.bind_tools()</code> method.
</li>
<li>
We define the tools we want to use - a search tool in our case. It is really easy to create your own tools - see documentation here on how to do that <a href="https://python.langchain.com/docs/how_to/custom_tools/">here</a>.
</li>
</ul>
</details>
<details>
<summary>Initialize graph with state.</summary>
<ul>
<li>We initialize graph (<code>StateGraph</code>) by passing state schema (in our case <code>MessagesState</code>)</li>
<li><code>MessagesState</code> is a prebuilt state schema that has one attribute -- a list of LangChain <code>Message</code> objects, as well as logic for merging the updates from each node into the state.</li>
</ul>
</details>
<details>
<summary>Define graph nodes.</summary>
There are two main nodes we need:
<ul>
<li>The <code>agent</code> node: responsible for deciding what (if any) actions to take.</li>
<li>The <code>tools</code> node that invokes tools: if the agent decides to take an action, this node will then execute that action.</li>
</ul>
</details>
<details>
<summary>Define entry point and graph edges.</summary>
First, we need to set the entry point for graph execution - <code>agent</code> node.
Then we define one normal and one conditional edge. Conditional edge means that the destination depends on the contents of the graph's state (<code>MessagesState</code>). In our case, the destination is not known until the agent (LLM) decides.
<ul>
<li>Conditional edge: after the agent is called, we should either:
<ul>
<li>a. Run tools if the agent said to take an action, OR</li>
<li>b. Finish (respond to the user) if the agent did not ask to run tools</li>
</ul>
</li>
<li>Normal edge: after the tools are invoked, the graph should always return to the agent to decide what to do next</li>
</ul>
</details>
<details>
<summary>Compile the graph.</summary>
<ul>
<li>
When we compile the graph, we turn it into a LangChain
<a href="https://python.langchain.com/docs/concepts/runnables/">Runnable</a>,
which automatically enables calling <code>.invoke()</code>, <code>.stream()</code> and <code>.batch()</code>
with your inputs
</li>
<li>
We can also optionally pass checkpointer object for persisting state between graph runs, and enabling memory,
human-in-the-loop workflows, time travel and more. In our case we use <code>MemorySaver</code> -
a simple in-memory checkpointer
</li>
</ul>
</details>
<details>
<summary>Execute the graph.</summary>
<ol>
<li>LangGraph adds the input message to the internal state, then passes the state to the entrypoint node, <code>"agent"</code>.</li>
<li>The <code>"agent"</code> node executes, invoking the chat model.</li>
<li>The chat model returns an <code>AIMessage</code>. LangGraph adds this to the state.</li>
<li>Graph cycles the following steps until there are no more <code>tool_calls</code> on <code>AIMessage</code>:
<ul>
<li>If <code>AIMessage</code> has <code>tool_calls</code>, <code>"tools"</code> node executes</li>
<li>The <code>"agent"</code> node executes again and returns <code>AIMessage</code></li>
</ul>
</li>
<li>Execution progresses to the special <code>END</code> value and outputs the final state. And as a result, we get a list of all our chat messages as output.</li>
</ol>
</details>
</details>
## Documentation
* [Tutorials](https://langchain-ai.github.io/langgraph/tutorials/): Learn to build with LangGraph through guided examples.
* [How-to Guides](https://langchain-ai.github.io/langgraph/how-tos/): Accomplish specific things within LangGraph, from streaming, to adding memory & persistence, to common design patterns (branching, subgraphs, etc.), these are the place to go if you want to copy and run a specific code snippet.
* [Conceptual Guides](https://langchain-ai.github.io/langgraph/concepts/high_level/): In-depth explanations of the key concepts and principles behind LangGraph, such as nodes, edges, state and more.
* [API Reference](https://langchain-ai.github.io/langgraph/reference/graphs/): Review important classes and methods, simple examples of how to use the graph and checkpointing APIs, higher-level prebuilt components and more.
* [LangGraph Platform](https://langchain-ai.github.io/langgraph/concepts/#langgraph-platform): LangGraph Platform is a commercial solution for deploying agentic applications in production, built on the open-source LangGraph framework.
## Resources
* [Built with LangGraph](https://www.langchain.com/built-with-langgraph): Hear how industry leaders use LangGraph to ship powerful, production-ready AI applications.
## Contributing
For more information on how to contribute, see [here](https://github.com/langchain-ai/langgraph/blob/main/CONTRIBUTING.md).
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.
+12 -13
View File
@@ -760,23 +760,22 @@ class CompiledStateGraph(CompiledGraph):
updates.extend(_get_updates(i) or ())
return updates
elif get_type_hints(type(input)):
# if input is a Pydantic model, only update values
# for the keys that have been explicitly set by the users
# (this is needed to avoid sending updates for fields with None defaults)
output_keys_ = output_keys
# Pydantic v2
if hasattr(input, "model_fields_set"):
output_keys_ = [
k for k in output_keys if k in input.model_fields_set
]
if hasattr(input, "model_fields"):
defaults = {k: v.default for k, v in input.model_fields.items()}
# Pydantic v1
elif hasattr(input, "__fields_set__"):
output_keys_ = [k for k in output_keys if k in input.__fields_set__]
elif hasattr(input, "__fields__"):
defaults = {k: v.default for k, v in input.__fields__.items()}
else:
defaults = {}
# if input is a Pydantic model, only update values
# that are different from the default values
return [
(k, getattr(input, k))
for k in output_keys_
if getattr(input, k, MISSING) is not MISSING
(k, value)
for k in output_keys
if (value := getattr(input, k, MISSING)) is not MISSING
and value != defaults.get(k)
]
else:
msg = create_error_message(
+3 -1
View File
@@ -1,4 +1,5 @@
from collections import ChainMap
from os import getenv
from typing import Any, Optional, Sequence, cast
from langchain_core.callbacks import (
@@ -11,7 +12,6 @@ from langchain_core.runnables import RunnableConfig
from langchain_core.runnables.config import (
CONFIG_KEYS,
COPIABLE_KEYS,
DEFAULT_RECURSION_LIMIT,
var_child_runnable_config,
)
@@ -26,6 +26,8 @@ from langgraph.constants import (
NS_SEP,
)
DEFAULT_RECURSION_LIMIT = int(getenv("LANGGRAPH_DEFAULT_RECURSION_LIMIT", "25"))
def recast_checkpoint_ns(ns: str) -> str:
"""Remove task IDs from checkpoint namespace.
+1 -1
View File
@@ -1,6 +1,6 @@
[tool.poetry]
name = "langgraph"
version = "0.3.7"
version = "0.3.8"
description = "Building stateful, multi-actor applications with LLMs"
authors = []
license = "MIT"
+34
View File
@@ -6658,6 +6658,40 @@ def test_pydantic_none_state_update() -> None:
assert graph.invoke({"foo": ""}) == {"foo": None}
def test_pydantic_state_mutation() -> None:
from pydantic import BaseModel, Field
class Inner(BaseModel):
a: int = 0
class State(BaseModel):
inner: Inner = Inner()
outer: int = 0
def my_node(state: State) -> State:
state.inner.a = 5
state.outer = 10
return state
graph = StateGraph(State).add_node(my_node).add_edge(START, "my_node").compile()
assert graph.invoke({"outer": 1}) == {"outer": 10, "inner": Inner(a=5)}
# test w/ default_factory
class State(BaseModel):
inner: Inner = Field(default_factory=Inner)
outer: int = 0
def my_node(state: State) -> State:
state.inner.a = 5
state.outer = 10
return state
graph = StateGraph(State).add_node(my_node).add_edge(START, "my_node").compile()
assert graph.invoke({"outer": 1}) == {"outer": 10, "inner": Inner(a=5)}
def test_get_stream_writer() -> None:
class State(TypedDict):
foo: str
@@ -257,7 +257,7 @@ def _validate_chat_history(
@_convert_modifier_to_prompt
def create_react_agent(
model: Union[str, LanguageModelLike],
tools: Union[Sequence[BaseTool], ToolNode],
tools: Union[Sequence[Union[BaseTool, Callable]], ToolNode],
*,
prompt: Optional[Prompt] = None,
response_format: Optional[
@@ -859,4 +859,7 @@ __all__ = [
"create_react_agent",
"create_tool_calling_executor",
"AgentState",
"AgentStatePydantic",
"AgentStateWithStructuredResponse",
"AgentStateWithStructuredResponsePydantic",
]
+1 -1
View File
@@ -1,6 +1,6 @@
[tool.poetry]
name = "langgraph-prebuilt"
version = "0.1.2"
version = "0.1.3"
description = "Library with high-level APIs for creating and executing LangGraph agents and tools."
authors = []
license = "MIT"
+1 -1
View File
@@ -1,6 +1,6 @@
{
"name": "@langchain/langgraph-sdk",
"version": "0.0.53",
"version": "0.0.54",
"description": "Client library for interacting with the LangGraph API",
"type": "module",
"packageManager": "yarn@1.22.19",
+7 -8
View File
@@ -115,6 +115,9 @@ interface LoadExternalComponentProps
/** Stream of the assistant */
stream: ReturnType<typeof useStream>;
/** Namespace of UI components. Defaults to assistant ID. */
namespace?: string;
/** UI message to be rendered */
message: UIMessage;
@@ -133,6 +136,7 @@ interface LoadExternalComponentProps
export function LoadExternalComponent({
stream,
namespace,
message,
meta,
fallback,
@@ -152,10 +156,11 @@ export function LoadExternalComponent({
const clientComponent = components?.[message.name];
const hasClientComponent = clientComponent != null;
const uiNamespace = namespace ?? stream.assistantId;
const uiClient = stream.client["~ui"];
React.useEffect(() => {
if (hasClientComponent) return;
uiClient.getComponent(stream.assistantId, message.name).then((html) => {
uiClient.getComponent(uiNamespace, message.name).then((html) => {
const dom = ref.current;
if (!dom) return;
const root = dom.shadowRoot ?? dom.attachShadow({ mode: "open" });
@@ -166,13 +171,7 @@ export function LoadExternalComponent({
);
root.appendChild(fragment);
});
}, [
uiClient,
stream.assistantId,
message.name,
shadowRootId,
hasClientComponent,
]);
}, [uiClient, uiNamespace, message.name, shadowRootId, hasClientComponent]);
if (hasClientComponent) {
return React.createElement(clientComponent, message.props);