Compare commits

..
Author SHA1 Message Date
Eugene Yurtsev 55880c9813 x 2025-07-27 16:41:25 -04:00
Eugene Yurtsev 22af613437 x 2025-07-27 16:24:58 -04:00
Eugene Yurtsev a254978893 x 2025-07-25 17:06:13 -04:00
22 changed files with 491 additions and 1105 deletions
+9
View File
@@ -35,7 +35,16 @@ jobs:
with:
filter: "docs/docs/**"
# TODO: Uncomment this to run on PRs
# run-changed-notebooks:
# needs: get-changed-files
# uses: ./.github/workflows/run_notebooks.yml
# secrets: inherit
# with:
# changed-files: ${{ needs.get-changed-files.outputs.changed-files }}
deploy:
# needs: run-changed-notebooks
runs-on: ubuntu-latest
timeout-minutes: 10 # Job will be cancelled if it runs for more than 10 minutes
env:
-1
View File
@@ -39,7 +39,6 @@ jobs:
scheduler-kafka
sdk-py
docs
ci
requireScope: false
ignoreLabels: |
ignore-lint-pr-title
+1 -3
View File
@@ -137,9 +137,7 @@ jobs:
needs:
- build
- release-notes
permissions:
contents: read
id-token: write
permissions: write-all
uses: ./.github/workflows/_test_release.yml
with:
working-directory: ${{ inputs.working-directory }}
+5 -10
View File
@@ -310,12 +310,6 @@ def _highlight_code_blocks(markdown: str) -> str:
return markdown
TARGET_LANGUAGE = os.environ.get("TARGET_LANGUAGE", "python")
if TARGET_LANGUAGE not in {"python", "js"}:
raise ValueError(f"TARGET_LANGUAGE must be 'python' or 'js', got {TARGET_LANGUAGE}")
def _on_page_markdown_with_config(
markdown: str,
page: Page,
@@ -338,15 +332,16 @@ def _on_page_markdown_with_config(
markdown = _highlight_code_blocks(markdown)
# Apply conditional rendering for code blocks
markdown = _apply_conditional_rendering(markdown, TARGET_LANGUAGE)
if TARGET_LANGUAGE == "js":
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":
elif target_language == "python":
# Via a dedicated plugin
pass
else:
raise ValueError(
f"Unsupported target language: {TARGET_LANGUAGE}. "
f"Unsupported target language: {target_language}. "
"Supported languages are 'python' and 'js'."
)
+6 -13
View File
@@ -8,7 +8,7 @@ Context includes *any* data outside the message list that can shape behavior. Th
- Internal state updated during a multi-step reasoning process.
- Persistent memory or facts from previous interactions.
LangGraph provides **three** primary ways to manage context:
LangGraph provides **three** primary ways to supply context:
| Type | Description | Mutable? | Lifetime |
|------------------------------------------------------------------------------|-----------------------------------------------|----------|-------------------------|
@@ -18,21 +18,14 @@ LangGraph provides **three** primary ways to manage context:
### Runtime Context
Runtime context is for immutable data like user metadata, tools, db connections, etc. Use this when you have values that don't change mid-run.
!!! note "`config['configurable']` -> `runtime.context`"
!!! version-added "New in LangGraph v0.6: `Runtime.context` replaces `config['configurable']`"
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.
The `Runtime` object is recommended to access static context and runtime-specific information like the store and stream writer.
As of LangGraph v1.0, the Runtime object is recommended to access static context and runtime-specific information like the store and stream writer.
!!! note
Runtime context refers to local context: data and dependencies your code needs to run. It does not refer to:
* The LLM context, which is the data passed into the LLM's prompt.
* The "context window", which is the maximum number of tokens that can be passed to the LLM.
You likely want to use the local context to optimize the LLM's context window. For example, you
could use a user id to fetch a user's name and information from a database to populate the context window with relevant memories.
Runtime context is for immutable data like user metadata or API keys. Use this when you have values that don't change mid-run.
Specify static context via the `context` argument to `invoke` / `stream`, which is reserved for this purpose:
@@ -4,22 +4,6 @@
---
## v0.2.109 (2025-07-28)
- Fixed an issue where missing config schema occurred when `config_type` was not set.
## v0.2.108 (2025-07-28)
- Added compatibility for langgraph v0.6, including new context API support and a migration to enhance context handling in assistant operations.
## v0.2.107 (2025-07-27)
- Implemented caching for authentication processes to improve performance.
- Merged count and select queries to improve database query efficiency.
## v0.2.106 (2025-07-27)
- Log whether run uses resumable streams.
## v0.2.105 (2025-07-27)
- Added a `/heapdump` endpoint to capture and save JS process heap data.
## v0.2.103 (2025-07-25)
- Corrected the metadata endpoint to ensure accurate data retrieval.
+1 -1
View File
@@ -28,7 +28,7 @@ To review, edit, and approve tool calls in an agent or workflow, [use LangGraph'
There are two ways to pause a graph:
- [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 pre-defined points, either before or after a node executes.
- [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.
<figure markdown="1">
![image](./img/breakpoints.png){: style="max-height:400px"}
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@@ -128,7 +128,7 @@ print(graph.invoke(Command(resume="Edited text"), config=config)) # (7)!
!!! tip "New in 0.4.0"
`__interrupt__` is a special key that will be returned when running the graph if the graph is interrupted. Support for `__interrupt__` in `invoke` and `ainvoke` has been added in version 0.4.0. If you're on an older version, you will only see `__interrupt__` in the result if you use `stream` or `astream`. You can also use `graph.get_state(thread_id)` to get the interrupt value(s).
`__interrupt__` is a special key that will be returned when running the graph if the graph is interrupted. Support for `__interrupt__` in `invoke` and `ainvoke` has been added in version 0.4.0. If you're on an older version, you will only see `__interrupt__` in the result if you use `stream` or `astream`. You can also use `graph.get_state(thread_id)` to get the interrupt value.
!!! warning
@@ -145,67 +145,19 @@ To resume execution, use the [`Command`][langgraph.types.Command] primitive, whi
graph.invoke(Command(resume={"age": "25"}), thread_config)
```
## Resuming Multiple interrupts
### Resume multiple interrupts with one invocation
When nodes with interrupt conditions are run in parallel, it's possible to have multiple interrupts in the task queue.
For example, the following graph has two nodes run in parallel that require human input:
<figure markdown="1">
![image](../assets/human_in_loop_parallel.png){: style="max-height:400px"}
</figure>
Once your graph has been interrupted and is stalled, you can resume all the interrupts at once with `Command.resume`, passing a dictionary mapping of interrupt ids to resume values.
If you have multiple interrupts in the task queue, you can use `Command.resume` with a dictionary mapping of interrupt ids to resume with a single `invoke` / `stream` call.
For example, once your graph has been interrupted (multiple times, theoretically) and is stalled:
```python
from typing import TypedDict
import uuid
from langchain_core.runnables import RunnableConfig
from langgraph.checkpoint.memory import InMemorySaver
from langgraph.constants import START
from langgraph.graph import StateGraph
from langgraph.types import interrupt, Command
class State(TypedDict):
text_1: str
text_2: str
def human_node_1(state: State):
value = interrupt({"text_to_revise": state["text_1"]})
return {"text_1": value}
def human_node_2(state: State):
value = interrupt({"text_to_revise": state["text_2"]})
return {"text_2": value}
graph_builder = StateGraph(State)
graph_builder.add_node("human_node_1", human_node_1)
graph_builder.add_node("human_node_2", human_node_2)
# Add both nodes in parallel from START
graph_builder.add_edge(START, "human_node_1")
graph_builder.add_edge(START, "human_node_2")
checkpointer = InMemorySaver()
graph = graph_builder.compile(checkpointer=checkpointer)
thread_id = str(uuid.uuid4())
config: RunnableConfig = {"configurable": {"thread_id": thread_id}}
result = graph.invoke(
{"text_1": "original text 1", "text_2": "original text 2"}, config=config
)
# Resume with mapping of interrupt IDs to values
resume_map = {
i.id: f"edited text for {i.value['text_to_revise']}"
for i in result["__interrupt__"]
i.id: f"human input for prompt {i.value}"
for i in parent.get_state(thread_config).interrupts
}
print(graph.invoke(Command(resume=resume_map), config=config))
# > {'text_1': 'edited text for original text 1', 'text_2': 'edited text for original text 2'}
parent_graph.invoke(Command(resume=resume_map), config=thread_config)
```
## Common patterns
@@ -1075,7 +1027,7 @@ def node_in_parent_graph(state: State):
{'parent_node': {'state_counter': 1}}
```
### Using multiple interrupts in a single node
### Using multiple interrupts
Using multiple interrupts within a **single** node can be helpful for patterns like [validating human input](#validate-human-input). However, using multiple interrupts in the same node can lead to unexpected behavior if not handled carefully.
+3 -112
View File
@@ -152,14 +152,6 @@ base64-js@^1.5.1:
resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.5.1.tgz#1b1b440160a5bf7ad40b650f095963481903930a"
integrity sha512-AKpaYlHn8t4SVbOHCy+b5+KKgvR4vrsD8vbvrbiQJps7fKDTkjkDry6ji0rUJjC0kzbNePLwzxq8iypo41qeWA==
call-bind-apply-helpers@^1.0.1, call-bind-apply-helpers@^1.0.2:
version "1.0.2"
resolved "https://registry.yarnpkg.com/call-bind-apply-helpers/-/call-bind-apply-helpers-1.0.2.tgz#4b5428c222be985d79c3d82657479dbe0b59b2d6"
integrity sha512-Sp1ablJ0ivDkSzjcaJdxEunN5/XvksFJ2sMBFfq6x0ryhQV/2b/KwFe21cMpmHtPOSij8K99/wSfoEuTObmuMQ==
dependencies:
es-errors "^1.3.0"
function-bind "^1.1.2"
camelcase@6:
version "6.3.0"
resolved "https://registry.yarnpkg.com/camelcase/-/camelcase-6.3.0.tgz#5685b95eb209ac9c0c177467778c9c84df58ba9a"
@@ -209,42 +201,6 @@ delayed-stream@~1.0.0:
resolved "https://registry.yarnpkg.com/delayed-stream/-/delayed-stream-1.0.0.tgz#df3ae199acadfb7d440aaae0b29e2272b24ec619"
integrity sha512-ZySD7Nf91aLB0RxL4KGrKHBXl7Eds1DAmEdcoVawXnLD7SDhpNgtuII2aAkg7a7QS41jxPSZ17p4VdGnMHk3MQ==
dunder-proto@^1.0.1:
version "1.0.1"
resolved "https://registry.yarnpkg.com/dunder-proto/-/dunder-proto-1.0.1.tgz#d7ae667e1dc83482f8b70fd0f6eefc50da30f58a"
integrity sha512-KIN/nDJBQRcXw0MLVhZE9iQHmG68qAVIBg9CqmUYjmQIhgij9U5MFvrqkUL5FbtyyzZuOeOt0zdeRe4UY7ct+A==
dependencies:
call-bind-apply-helpers "^1.0.1"
es-errors "^1.3.0"
gopd "^1.2.0"
es-define-property@^1.0.1:
version "1.0.1"
resolved "https://registry.yarnpkg.com/es-define-property/-/es-define-property-1.0.1.tgz#983eb2f9a6724e9303f61addf011c72e09e0b0fa"
integrity sha512-e3nRfgfUZ4rNGL232gUgX06QNyyez04KdjFrF+LTRoOXmrOgFKDg4BCdsjW8EnT69eqdYGmRpJwiPVYNrCaW3g==
es-errors@^1.3.0:
version "1.3.0"
resolved "https://registry.yarnpkg.com/es-errors/-/es-errors-1.3.0.tgz#05f75a25dab98e4fb1dcd5e1472c0546d5057c8f"
integrity sha512-Zf5H2Kxt2xjTvbJvP2ZWLEICxA6j+hAmMzIlypy4xcBg1vKVnx89Wy0GbS+kf5cwCVFFzdCFh2XSCFNULS6csw==
es-object-atoms@^1.0.0, es-object-atoms@^1.1.1:
version "1.1.1"
resolved "https://registry.yarnpkg.com/es-object-atoms/-/es-object-atoms-1.1.1.tgz#1c4f2c4837327597ce69d2ca190a7fdd172338c1"
integrity sha512-FGgH2h8zKNim9ljj7dankFPcICIK9Cp5bm+c2gQSYePhpaG5+esrLODihIorn+Pe6FGJzWhXQotPv73jTaldXA==
dependencies:
es-errors "^1.3.0"
es-set-tostringtag@^2.1.0:
version "2.1.0"
resolved "https://registry.yarnpkg.com/es-set-tostringtag/-/es-set-tostringtag-2.1.0.tgz#f31dbbe0c183b00a6d26eb6325c810c0fd18bd4d"
integrity sha512-j6vWzfrGVfyXxge+O0x5sh6cvxAog0a/4Rdd2K36zCMV5eJ+/+tOAngRO8cODMNWbVRdVlmGZQL2YS3yR8bIUA==
dependencies:
es-errors "^1.3.0"
get-intrinsic "^1.2.6"
has-tostringtag "^1.0.2"
hasown "^2.0.2"
event-lite@^0.1.1:
version "0.1.3"
resolved "https://registry.yarnpkg.com/event-lite/-/event-lite-0.1.3.tgz#3dfe01144e808ac46448f0c19b4ab68e403a901d"
@@ -266,14 +222,12 @@ form-data-encoder@1.7.2:
integrity sha512-qfqtYan3rxrnCk1VYaA4H+Ms9xdpPqvLZa6xmMgFvhO32x7/3J/ExcTd6qpxM0vH2GdMI+poehyBZvqfMTto8A==
form-data@^4.0.0:
version "4.0.4"
resolved "https://registry.yarnpkg.com/form-data/-/form-data-4.0.4.tgz#784cdcce0669a9d68e94d11ac4eea98088edd2c4"
integrity sha512-KrGhL9Q4zjj0kiUt5OO4Mr/A/jlI2jDYs5eHBpYHPcBEVSiipAvn2Ko2HnPe20rmcuuvMHNdZFp+4IlGTMF0Ow==
version "4.0.1"
resolved "https://registry.yarnpkg.com/form-data/-/form-data-4.0.1.tgz#ba1076daaaa5bfd7e99c1a6cb02aa0a5cff90d48"
integrity sha512-tzN8e4TX8+kkxGPK8D5u0FNmjPUjw3lwC9lSLxxoB/+GtsJG91CO8bSWy73APlgAZzZbXEYZJuxjkHH2w+Ezhw==
dependencies:
asynckit "^0.4.0"
combined-stream "^1.0.8"
es-set-tostringtag "^2.1.0"
hasown "^2.0.2"
mime-types "^2.1.12"
formdata-node@^4.3.2:
@@ -284,69 +238,11 @@ formdata-node@^4.3.2:
node-domexception "1.0.0"
web-streams-polyfill "4.0.0-beta.3"
function-bind@^1.1.2:
version "1.1.2"
resolved "https://registry.yarnpkg.com/function-bind/-/function-bind-1.1.2.tgz#2c02d864d97f3ea6c8830c464cbd11ab6eab7a1c"
integrity sha512-7XHNxH7qX9xG5mIwxkhumTox/MIRNcOgDrxWsMt2pAr23WHp6MrRlN7FBSFpCpr+oVO0F744iUgR82nJMfG2SA==
get-intrinsic@^1.2.6:
version "1.3.0"
resolved "https://registry.yarnpkg.com/get-intrinsic/-/get-intrinsic-1.3.0.tgz#743f0e3b6964a93a5491ed1bffaae054d7f98d01"
integrity sha512-9fSjSaos/fRIVIp+xSJlE6lfwhES7LNtKaCBIamHsjr2na1BiABJPo0mOjjz8GJDURarmCPGqaiVg5mfjb98CQ==
dependencies:
call-bind-apply-helpers "^1.0.2"
es-define-property "^1.0.1"
es-errors "^1.3.0"
es-object-atoms "^1.1.1"
function-bind "^1.1.2"
get-proto "^1.0.1"
gopd "^1.2.0"
has-symbols "^1.1.0"
hasown "^2.0.2"
math-intrinsics "^1.1.0"
get-proto@^1.0.1:
version "1.0.1"
resolved "https://registry.yarnpkg.com/get-proto/-/get-proto-1.0.1.tgz#150b3f2743869ef3e851ec0c49d15b1d14d00ee1"
integrity sha512-sTSfBjoXBp89JvIKIefqw7U2CCebsc74kiY6awiGogKtoSGbgjYE/G/+l9sF3MWFPNc9IcoOC4ODfKHfxFmp0g==
dependencies:
dunder-proto "^1.0.1"
es-object-atoms "^1.0.0"
gopd@^1.2.0:
version "1.2.0"
resolved "https://registry.yarnpkg.com/gopd/-/gopd-1.2.0.tgz#89f56b8217bdbc8802bd299df6d7f1081d7e51a1"
integrity sha512-ZUKRh6/kUFoAiTAtTYPZJ3hw9wNxx+BIBOijnlG9PnrJsCcSjs1wyyD6vJpaYtgnzDrKYRSqf3OO6Rfa93xsRg==
has-flag@^4.0.0:
version "4.0.0"
resolved "https://registry.yarnpkg.com/has-flag/-/has-flag-4.0.0.tgz#944771fd9c81c81265c4d6941860da06bb59479b"
integrity sha512-EykJT/Q1KjTWctppgIAgfSO0tKVuZUjhgMr17kqTumMl6Afv3EISleU7qZUzoXDFTAHTDC4NOoG/ZxU3EvlMPQ==
has-symbols@^1.0.3, has-symbols@^1.1.0:
version "1.1.0"
resolved "https://registry.yarnpkg.com/has-symbols/-/has-symbols-1.1.0.tgz#fc9c6a783a084951d0b971fe1018de813707a338"
integrity sha512-1cDNdwJ2Jaohmb3sg4OmKaMBwuC48sYni5HUw2DvsC8LjGTLK9h+eb1X6RyuOHe4hT0ULCW68iomhjUoKUqlPQ==
has-tostringtag@^1.0.2:
version "1.0.2"
resolved "https://registry.yarnpkg.com/has-tostringtag/-/has-tostringtag-1.0.2.tgz#2cdc42d40bef2e5b4eeab7c01a73c54ce7ab5abc"
integrity sha512-NqADB8VjPFLM2V0VvHUewwwsw0ZWBaIdgo+ieHtK3hasLz4qeCRjYcqfB6AQrBggRKppKF8L52/VqdVsO47Dlw==
dependencies:
has-symbols "^1.0.3"
hasown@^2.0.2:
version "2.0.2"
resolved "https://registry.yarnpkg.com/hasown/-/hasown-2.0.2.tgz#003eaf91be7adc372e84ec59dc37252cedb80003"
integrity sha512-0hJU9SCPvmMzIBdZFqNPXWa6dqh7WdH0cII9y+CyS8rG3nL48Bclra9HmKhVVUHyPWNH5Y7xDwAB7bfgSjkUMQ==
dependencies:
function-bind "^1.1.2"
he@^1.2.0:
version "1.2.0"
resolved "https://registry.yarnpkg.com/he/-/he-1.2.0.tgz#84ae65fa7eafb165fddb61566ae14baf05664f0f"
integrity sha512-F/1DnUGPopORZi0ni+CvrCgHQ5FyEAHRLSApuYWMmrbSwoN2Mn/7k+Gl38gJnR7yyDZk6WLXwiGod1JOWNDKGw==
humanize-ms@^1.2.1:
version "1.2.1"
resolved "https://registry.yarnpkg.com/humanize-ms/-/humanize-ms-1.2.1.tgz#c46e3159a293f6b896da29316d8b6fe8bb79bbed"
@@ -399,11 +295,6 @@ json-stringify-safe@^5.0.1:
semver "^7.6.3"
uuid "^10.0.0"
math-intrinsics@^1.1.0:
version "1.1.0"
resolved "https://registry.yarnpkg.com/math-intrinsics/-/math-intrinsics-1.1.0.tgz#a0dd74be81e2aa5c2f27e65ce283605ee4e2b7f9"
integrity sha512-/IXtbwEk5HTPyEwyKX6hGkYXxM9nbj64B+ilVJnC/R6B0pH5G4V3b0pVbL7DBj4tkhBAppbQUlf6F6Xl9LHu1g==
mime-db@1.52.0:
version "1.52.0"
resolved "https://registry.yarnpkg.com/mime-db/-/mime-db-1.52.0.tgz#bbabcdc02859f4987301c856e3387ce5ec43bf70"
+1 -1
View File
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
[project]
name = "langgraph-checkpoint-sqlite"
version = "2.0.11"
version = "2.0.10"
description = "Library with a SQLite implementation of LangGraph checkpoint saver."
authors = []
requires-python = ">=3.9"
+1 -1
View File
@@ -346,7 +346,7 @@ dev = [
[[package]]
name = "langgraph-checkpoint-sqlite"
version = "2.0.11"
version = "2.0.10"
source = { editable = "." }
dependencies = [
{ name = "aiosqlite" },
@@ -1 +0,0 @@
"""Legacy utilities module, to be removed in v1."""
-4
View File
@@ -1,4 +0,0 @@
"""Backwards compat imports for config utilities, to be removed in v1."""
from langgraph._internal._config import ensure_config, patch_configurable # noqa: F401
from langgraph.config import get_config, get_store # noqa: F401
@@ -1,3 +0,0 @@
"""Backwards compat imports for runnable utilities, to be removed in v1."""
from langgraph._internal._runnable import RunnableCallable, RunnableLike # noqa: F401
+1 -1
View File
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
[project]
name = "langgraph"
version = "0.6.0"
version = "0.6.0a1"
description = "Building stateful, multi-actor applications with LLMs"
authors = []
requires-python = ">=3.9"
View File
+2
View File
@@ -0,0 +1,2 @@
# import for backwards compatibility
from langgraph._internal._runnable import RunnableCallable, RunnableSeq # noqa: F401
+2 -2
View File
@@ -1192,7 +1192,7 @@ wheels = [
[[package]]
name = "langgraph"
version = "0.6.0"
version = "0.6.0a1"
source = { editable = "." }
dependencies = [
{ name = "langchain-core" },
@@ -1364,7 +1364,7 @@ dev = [
[[package]]
name = "langgraph-checkpoint-sqlite"
version = "2.0.11"
version = "2.0.10"
source = { editable = "../checkpoint-sqlite" }
dependencies = [
{ name = "aiosqlite" },
@@ -1,7 +1,6 @@
import inspect
from typing import (
Any,
Awaitable,
Callable,
Literal,
Optional,
@@ -45,10 +44,8 @@ from langgraph.graph.state import CompiledStateGraph
from langgraph.managed import IsLastStep, RemainingSteps
from langgraph.prebuilt._internal import ToolCallWithContext
from langgraph.prebuilt.tool_node import ToolNode
from langgraph.runtime import Runtime
from langgraph.store.base import BaseStore
from langgraph.types import Checkpointer, Send
from langgraph.typing import ContextT
from langgraph.warnings import LangGraphDeprecatedSinceV10
StructuredResponse = Union[dict, BaseModel]
@@ -248,13 +245,437 @@ def _validate_chat_history(
raise ValueError(error_message)
class _AgentBuilder:
"""Internal builder class for constructing React agents with intuitive method-to-node mapping."""
def __init__(
self,
model: Union[str, LanguageModelLike],
tools: Union[Sequence[Union[BaseTool, Callable, dict[str, Any]]], ToolNode],
*,
prompt: Optional[Prompt] = None,
response_format: Optional[
Union[StructuredResponseSchema, tuple[str, StructuredResponseSchema]]
] = None,
pre_model_hook: Optional[RunnableLike] = None,
post_model_hook: Optional[RunnableLike] = None,
state_schema: Optional[StateSchemaType] = None,
context_schema: Optional[Type[Any]] = None,
version: Literal["v1", "v2"] = "v2",
name: Optional[str] = None,
):
# Store all parameters
self.model = model
self.tools = tools
self.prompt = prompt
self.response_format = response_format
self.pre_model_hook = pre_model_hook
self.post_model_hook = post_model_hook
self.state_schema = state_schema
self.context_schema = context_schema
self.version = version
self.name = name
# Setup tools
if isinstance(self.tools, ToolNode):
self._tool_classes = list(self.tools.tools_by_name.values())
self._tool_node = self.tools
else:
self._llm_builtin_tools = [t for t in self.tools if isinstance(t, dict)]
self._tool_node = ToolNode(
[t for t in self.tools if not isinstance(t, dict)]
)
self._tool_classes = list(self._tool_node.tools_by_name.values())
self._should_return_direct: set[str] = {
t.name for t in self._tool_classes if t.return_direct
}
# Setup state schema
if self.state_schema is not None:
required_keys = {"messages", "remaining_steps"}
if self.response_format is not None:
required_keys.add("structured_response")
schema_keys = set(get_type_hints(self.state_schema))
if missing_keys := required_keys - schema_keys:
raise ValueError(
f"Missing required key(s) {missing_keys} in state_schema"
)
self._final_state_schema = self.state_schema
else:
self._final_state_schema = (
AgentStateWithStructuredResponse
if self.response_format is not None
else AgentState
)
# Setup model
model = self.model
# Convert string models
if isinstance(model, str):
try:
from langchain.chat_models import init_chat_model # type: ignore[import-not-found]
except ImportError:
raise ImportError(
"Please install langchain (`pip install langchain`) to use '<provider>:<model>' string syntax for `model` parameter."
)
model = cast(BaseChatModel, init_chat_model(model))
# Bind tools if needed
if (
_should_bind_tools(
model, self._tool_classes, num_builtin=len(self._llm_builtin_tools)
)
and len(self._tool_classes + self._llm_builtin_tools) > 0
):
model = cast(BaseChatModel, model).bind_tools(
self._tool_classes + self._llm_builtin_tools
) # type: ignore[operator]
self._model_runnable = _get_prompt_runnable(self.prompt) | model
def create_model_node(self) -> RunnableCallable:
"""Create the 'agent' node that calls the LLM."""
def _get_model_input_state(state: StateSchema) -> StateSchema:
if self.pre_model_hook is not None:
messages: Optional[Sequence[BaseMessage]] = (
_get_state_value(state, "llm_input_messages")
) or _get_state_value(state, "messages")
error_msg: str = f"Expected input to call_model to have 'llm_input_messages' or 'messages' key, but got {state}"
else:
messages = _get_state_value(state, "messages")
error_msg = f"Expected input to call_model to have 'messages' key, but got {state}"
if messages is None:
raise ValueError(error_msg)
_validate_chat_history(messages)
if isinstance(self._final_state_schema, type) and issubclass(
self._final_state_schema, BaseModel
):
state.messages = messages # type: ignore
else:
state["messages"] = messages # type: ignore
return state
def _are_more_steps_needed(state: StateSchema, response: BaseMessage) -> bool:
has_tool_calls = isinstance(response, AIMessage) and response.tool_calls
all_tools_return_direct = (
all(
call["name"] in self._should_return_direct
for call in response.tool_calls
)
if isinstance(response, AIMessage)
else False
)
remaining_steps = _get_state_value(state, "remaining_steps", None)
is_last_step = _get_state_value(state, "is_last_step", False)
return (
(remaining_steps is None and is_last_step and has_tool_calls)
or (
remaining_steps is not None
and remaining_steps < 1
and all_tools_return_direct
)
or (
remaining_steps is not None
and remaining_steps < 2
and has_tool_calls
)
)
def call_model(state: StateSchema, config: RunnableConfig) -> StateSchema:
state = _get_model_input_state(state)
response = cast(AIMessage, self._model_runnable.invoke(state, config)) # type: ignore[union-attr]
response.name = self.name
if _are_more_steps_needed(state, response):
return {
"messages": [
AIMessage(
id=response.id,
content="Sorry, need more steps to process this request.",
)
]
}
return {"messages": [response]}
async def acall_model(
state: StateSchema, config: RunnableConfig
) -> StateSchema:
state = _get_model_input_state(state)
response = cast(
AIMessage, await self._model_runnable.ainvoke(state, config)
) # type: ignore[union-attr]
response.name = self.name
if _are_more_steps_needed(state, response):
return {
"messages": [
AIMessage(
id=response.id,
content="Sorry, need more steps to process this request.",
)
]
}
return {"messages": [response]}
# Determine input schema
input_schema = self._final_state_schema
if self.pre_model_hook is not None:
if isinstance(self._final_state_schema, type) and issubclass(
self._final_state_schema, BaseModel
):
from pydantic import create_model
input_schema = create_model(
"CallModelInputSchema",
llm_input_messages=(list[AnyMessage], ...),
__base__=self._final_state_schema,
)
else:
class CallModelInputSchema(self._final_state_schema): # type: ignore
llm_input_messages: list[AnyMessage]
input_schema = CallModelInputSchema
return RunnableCallable(call_model, acall_model, input_schema=input_schema)
def create_structured_response_node(self) -> Optional[RunnableCallable]:
"""Create the 'generate_structured_response' node if configured."""
if self.response_format is None:
return None
def generate_structured_response(
state: StateSchema, config: RunnableConfig
) -> StateSchema:
messages = _get_state_value(state, "messages")
structured_response_schema = self.response_format
if isinstance(self.response_format, tuple):
system_prompt, structured_response_schema = self.response_format
messages = [SystemMessage(content=system_prompt)] + list(messages)
model_with_structured_output = _get_model(
self._model_runnable
).with_structured_output( # type: ignore[arg-type]
cast(StructuredResponseSchema, structured_response_schema)
)
response = model_with_structured_output.invoke(messages, config)
return {"structured_response": response}
async def agenerate_structured_response(
state: StateSchema, config: RunnableConfig
) -> StateSchema:
messages = _get_state_value(state, "messages")
structured_response_schema = self.response_format
if isinstance(self.response_format, tuple):
system_prompt, structured_response_schema = self.response_format
messages = [SystemMessage(content=system_prompt)] + list(messages)
model_with_structured_output = _get_model(
self._model_runnable
).with_structured_output( # type: ignore[arg-type]
cast(StructuredResponseSchema, structured_response_schema)
)
response = await model_with_structured_output.ainvoke(messages, config)
return {"structured_response": response}
return RunnableCallable(
generate_structured_response, agenerate_structured_response
)
def create_model_router(self) -> Callable[[StateSchema], Union[str, list[Send]]]:
"""Create routing function for model node conditional edges."""
def should_continue(state: StateSchema) -> Union[str, list[Send]]:
messages = _get_state_value(state, "messages")
last_message = messages[-1]
if not isinstance(last_message, AIMessage) or not last_message.tool_calls:
if self.post_model_hook is not None:
return "post_model_hook"
elif self.response_format is not None:
return "generate_structured_response"
else:
return END
else:
if self.version == "v1":
return "tools"
elif self.version == "v2":
if self.post_model_hook is not None:
return "post_model_hook"
return [
Send(
"tools",
ToolCallWithContext(
__type="tool_call_with_context",
tool_call=tool_call,
state=state,
),
)
for tool_call in last_message.tool_calls
]
return should_continue
def post_model_hook_router(self, state: StateSchema) -> Union[str, list[Send]]:
"""Route to the next node after post_model_hook."""
messages = _get_state_value(state, "messages")
tool_messages = [m.tool_call_id for m in messages if isinstance(m, ToolMessage)]
last_ai_message = next(
m for m in reversed(messages) if isinstance(m, AIMessage)
)
pending_tool_calls = [
c for c in last_ai_message.tool_calls if c["id"] not in tool_messages
]
if pending_tool_calls:
return [
Send(
"tools",
ToolCallWithContext(
__type="tool_call_with_context",
tool_call=tool_call,
state=state,
),
)
for tool_call in pending_tool_calls
]
elif isinstance(messages[-1], ToolMessage):
return self._get_entry_point()
elif self.response_format is not None:
return "generate_structured_response"
else:
return END
def create_tools_router(self) -> Optional[Callable[[StateSchema], str]]:
"""Create routing function for tools node conditional edges."""
if not self._should_return_direct:
return None
def route_tool_responses(state: StateSchema) -> str:
messages = _get_state_value(state, "messages")
for m in reversed(messages):
if not isinstance(m, ToolMessage):
break
if m.name in self._should_return_direct:
return END
if isinstance(m, AIMessage) and m.tool_calls:
if any(
call["name"] in self._should_return_direct for call in m.tool_calls
):
return END
return self._get_entry_point()
return route_tool_responses
def _get_entry_point(self) -> str:
"""Get the workflow entry point."""
return "pre_model_hook" if self.pre_model_hook else "agent"
def _has_tools(self) -> bool:
"""Check if agent has tools enabled."""
return len(self._tool_classes) > 0
def _get_model_edges(self) -> list[str]:
"""Get possible edge destinations from model node."""
edges = []
# If post_model_hook exists, we don't add edges here - we use direct edge instead
if not self.post_model_hook:
if self._has_tools():
edges.append("tools")
if self.response_format:
edges.append("generate_structured_response")
if not self._has_tools() and not self.response_format:
edges.append(END)
return edges
def _get_post_model_hook_edges(self) -> list[str]:
"""Get possible edge destinations from post_model_hook node."""
edges = [self._get_entry_point()]
if self._has_tools():
edges.append("tools")
if self.response_format:
edges.append("generate_structured_response")
else:
edges.append(END)
return edges
def build(self) -> StateGraph:
"""Build the agent workflow graph (uncompiled)."""
# Create workflow
workflow = StateGraph(
state_schema=self._final_state_schema, # type: ignore[arg-type]
context_schema=self.context_schema,
)
# Add nodes
# Always add model node (named 'agent' for backwards compatibility)
workflow.add_node("agent", self.create_model_node())
# Add tools node if needed
if self._has_tools():
workflow.add_node("tools", self._tool_node)
# Add hook nodes if configured
if self.pre_model_hook:
workflow.add_node("pre_model_hook", self.pre_model_hook) # type: ignore[arg-type]
if self.post_model_hook:
workflow.add_node("post_model_hook", self.post_model_hook) # type: ignore[arg-type]
# Add structured response node if configured
structured_node = self.create_structured_response_node()
if structured_node:
workflow.add_node("generate_structured_response", structured_node)
# Add edges
entry_point = self._get_entry_point()
workflow.set_entry_point(entry_point)
# Pre-model hook edge
if self.pre_model_hook:
workflow.add_edge("pre_model_hook", "agent")
# Model node edges
if self.post_model_hook:
# Direct edge from model node to post_model_hook when post_model_hook exists
workflow.add_edge("agent", "post_model_hook")
# Post-model hook conditional edges
post_hook_edges = self._get_post_model_hook_edges()
workflow.add_conditional_edges(
"post_model_hook", self.post_model_hook_router, path_map=post_hook_edges
) # type: ignore[arg-type]
else:
# Conditional edges from model node when no post_model_hook
model_router = self.create_model_router()
model_edges = self._get_model_edges()
workflow.add_conditional_edges("agent", model_router, path_map=model_edges) # type: ignore[arg-type]
# Tools edges
if self._has_tools():
tools_router = self.create_tools_router()
if tools_router:
workflow.add_conditional_edges(
"tools", tools_router, path_map=[entry_point, END]
)
else:
workflow.add_edge("tools", entry_point)
return workflow
def create_react_agent(
model: Union[
str,
LanguageModelLike,
Callable[[StateSchema, Runtime[ContextT]], BaseChatModel],
Callable[[StateSchema, Runtime[ContextT]], Awaitable[BaseChatModel]],
],
model: Union[str, LanguageModelLike],
tools: Union[Sequence[Union[BaseTool, Callable, dict[str, Any]]], ToolNode],
*,
prompt: Optional[Prompt] = None,
@@ -279,43 +700,7 @@ def create_react_agent(
For more details on using `create_react_agent`, visit [Agents](https://langchain-ai.github.io/langgraph/agents/overview/) documentation.
Args:
model: The language model for the agent. Supports static and dynamic
model selection.
- **Static model**: A chat model instance (e.g., `ChatOpenAI()`) or
string identifier (e.g., `"openai:gpt-4"`)
- **Dynamic model**: A callable with signature
`(state, runtime) -> BaseChatModel` that returns different models
based on runtime context
Dynamic functions receive graph state and runtime, enabling
context-dependent model selection. Must return a `BaseChatModel`
instance. For tool calling, bind tools using `.bind_tools()`.
Bound tools must be a subset of the `tools` parameter.
Dynamic model example:
```python
from dataclasses import dataclass
@dataclass
class ModelContext:
model_name: str = "gpt-3.5-turbo"
# Instantiate models globally
gpt4_model = ChatOpenAI(model="gpt-4")
gpt35_model = ChatOpenAI(model="gpt-3.5-turbo")
def select_model(state: AgentState, runtime: Runtime[ModelContext]) -> ChatOpenAI:
model_name = runtime.context.model_name
model = gpt4_model if model_name == "gpt-4" else gpt35_model
return model.bind_tools(tools)
```
!!! note "Dynamic Model Requirements"
Ensure returned models have appropriate tools bound via
`.bind_tools()` and support required functionality. Bound tools
must be a subset of those specified in the `tools` parameter.
model: The `LangChain` chat model that supports tool calling.
tools: A list of tools or a ToolNode instance.
If an empty list is provided, the agent will consist of a single LLM node without tool calling.
prompt: An optional prompt for the LLM. Can take a few different forms:
@@ -455,6 +840,7 @@ def create_react_agent(
print(chunk)
```
"""
# Handle deprecated config_schema parameter
if (
config_schema := deprecated_kwargs.pop("config_schema", MISSING)
) is not MISSING:
@@ -466,471 +852,29 @@ def create_react_agent(
if context_schema is not None:
context_schema = config_schema
# Validate version
if version not in ("v1", "v2"):
raise ValueError(
f"Invalid version {version}. Supported versions are 'v1' and 'v2'."
)
if state_schema is not None:
required_keys = {"messages", "remaining_steps"}
if response_format is not None:
required_keys.add("structured_response")
schema_keys = set(get_type_hints(state_schema))
if missing_keys := required_keys - set(schema_keys):
raise ValueError(f"Missing required key(s) {missing_keys} in state_schema")
if state_schema is None:
state_schema = (
AgentStateWithStructuredResponse
if response_format is not None
else AgentState
)
llm_builtin_tools: list[dict] = []
if isinstance(tools, ToolNode):
tool_classes = list(tools.tools_by_name.values())
tool_node = tools
else:
llm_builtin_tools = [t for t in tools if isinstance(t, dict)]
tool_node = ToolNode([t for t in tools if not isinstance(t, dict)])
tool_classes = list(tool_node.tools_by_name.values())
is_dynamic_model = not isinstance(model, (str, Runnable)) and callable(model)
is_async_dynamic_model = is_dynamic_model and inspect.iscoroutinefunction(model)
tool_calling_enabled = len(tool_classes) > 0
if not is_dynamic_model:
if isinstance(model, str):
try:
from langchain.chat_models import ( # type: ignore[import-not-found]
init_chat_model,
)
except ImportError:
raise ImportError(
"Please install langchain (`pip install langchain`) to "
"use '<provider>:<model>' string syntax for `model` parameter."
)
model = cast(BaseChatModel, init_chat_model(model))
if (
_should_bind_tools(model, tool_classes, num_builtin=len(llm_builtin_tools)) # type: ignore[arg-type]
and len(tool_classes + llm_builtin_tools) > 0
):
model = cast(BaseChatModel, model).bind_tools(
tool_classes + llm_builtin_tools # type: ignore[operator]
)
static_model: Optional[Runnable] = _get_prompt_runnable(prompt) | model # type: ignore[operator]
else:
# For dynamic models, we'll create the runnable at runtime
static_model = None
# If any of the tools are configured to return_directly after running,
# our graph needs to check if these were called
should_return_direct = {t.name for t in tool_classes if t.return_direct}
def _resolve_model(
state: StateSchema, runtime: Runtime[ContextT]
) -> LanguageModelLike:
"""Resolve the model to use, handling both static and dynamic models."""
if is_dynamic_model:
return _get_prompt_runnable(prompt) | model(state, runtime) # type: ignore[operator]
else:
return static_model
async def _aresolve_model(
state: StateSchema, runtime: Runtime[ContextT]
) -> LanguageModelLike:
"""Async resolve the model to use, handling both static and dynamic models."""
if is_async_dynamic_model:
resolved_model = await model(state, runtime) # type: ignore[misc,operator]
return _get_prompt_runnable(prompt) | resolved_model
elif is_dynamic_model:
return _get_prompt_runnable(prompt) | model(state, runtime) # type: ignore[operator]
else:
return static_model
def _are_more_steps_needed(state: StateSchema, response: BaseMessage) -> bool:
has_tool_calls = isinstance(response, AIMessage) and response.tool_calls
all_tools_return_direct = (
all(call["name"] in should_return_direct for call in response.tool_calls)
if isinstance(response, AIMessage)
else False
)
remaining_steps = _get_state_value(state, "remaining_steps", None)
is_last_step = _get_state_value(state, "is_last_step", False)
return (
(remaining_steps is None and is_last_step and has_tool_calls)
or (
remaining_steps is not None
and remaining_steps < 1
and all_tools_return_direct
)
or (remaining_steps is not None and remaining_steps < 2 and has_tool_calls)
)
def _get_model_input_state(state: StateSchema) -> StateSchema:
if pre_model_hook is not None:
messages = (
_get_state_value(state, "llm_input_messages")
) or _get_state_value(state, "messages")
error_msg = f"Expected input to call_model to have 'llm_input_messages' or 'messages' key, but got {state}"
else:
messages = _get_state_value(state, "messages")
error_msg = (
f"Expected input to call_model to have 'messages' key, but got {state}"
)
if messages is None:
raise ValueError(error_msg)
_validate_chat_history(messages)
# we're passing messages under `messages` key, as this is expected by the prompt
if isinstance(state_schema, type) and issubclass(state_schema, BaseModel):
state.messages = messages # type: ignore
else:
state["messages"] = messages # type: ignore
return state
# Define the function that calls the model
def call_model(
state: StateSchema, runtime: Runtime[ContextT], config: RunnableConfig
) -> StateSchema:
if is_async_dynamic_model:
msg = (
"Async model callable provided but agent invoked synchronously. "
"Use agent.ainvoke() or agent.astream(), or "
"provide a sync model callable."
)
raise RuntimeError(msg)
model_input = _get_model_input_state(state)
if is_dynamic_model:
# Resolve dynamic model at runtime and apply prompt
dynamic_model = _resolve_model(state, runtime)
response = cast(AIMessage, dynamic_model.invoke(model_input, config)) # type: ignore[arg-type]
else:
response = cast(AIMessage, static_model.invoke(model_input, config)) # type: ignore[union-attr]
# add agent name to the AIMessage
response.name = name
if _are_more_steps_needed(state, response):
return {
"messages": [
AIMessage(
id=response.id,
content="Sorry, need more steps to process this request.",
)
]
}
# We return a list, because this will get added to the existing list
return {"messages": [response]}
async def acall_model(
state: StateSchema, runtime: Runtime[ContextT], config: RunnableConfig
) -> StateSchema:
model_input = _get_model_input_state(state)
if is_dynamic_model:
# Resolve dynamic model at runtime and apply prompt
# (supports both sync and async)
dynamic_model = await _aresolve_model(state, runtime)
response = cast(AIMessage, await dynamic_model.ainvoke(model_input, config)) # type: ignore[arg-type]
else:
response = cast(AIMessage, await static_model.ainvoke(model_input, config)) # type: ignore[union-attr]
# add agent name to the AIMessage
response.name = name
if _are_more_steps_needed(state, response):
return {
"messages": [
AIMessage(
id=response.id,
content="Sorry, need more steps to process this request.",
)
]
}
# We return a list, because this will get added to the existing list
return {"messages": [response]}
input_schema: StateSchemaType
if pre_model_hook is not None:
# Dynamically create a schema that inherits from state_schema and adds 'llm_input_messages'
if isinstance(state_schema, type) and issubclass(state_schema, BaseModel):
# For Pydantic schemas
from pydantic import create_model
input_schema = create_model(
"CallModelInputSchema",
llm_input_messages=(list[AnyMessage], ...),
__base__=state_schema,
)
else:
# For TypedDict schemas
class CallModelInputSchema(state_schema): # type: ignore
llm_input_messages: list[AnyMessage]
input_schema = CallModelInputSchema
else:
input_schema = state_schema
def generate_structured_response(
state: StateSchema, runtime: Runtime[ContextT], config: RunnableConfig
) -> StateSchema:
if is_async_dynamic_model:
msg = (
"Async model callable provided but agent invoked synchronously. "
"Use agent.ainvoke() or agent.astream(), or provide a sync model callable."
)
raise RuntimeError(msg)
messages = _get_state_value(state, "messages")
structured_response_schema = response_format
if isinstance(response_format, tuple):
system_prompt, structured_response_schema = response_format
messages = [SystemMessage(content=system_prompt)] + list(messages)
resolved_model = _resolve_model(state, runtime)
model_with_structured_output = _get_model(
resolved_model
).with_structured_output(
cast(StructuredResponseSchema, structured_response_schema)
)
response = model_with_structured_output.invoke(messages, config)
return {"structured_response": response}
async def agenerate_structured_response(
state: StateSchema, runtime: Runtime[ContextT], config: RunnableConfig
) -> StateSchema:
messages = _get_state_value(state, "messages")
structured_response_schema = response_format
if isinstance(response_format, tuple):
system_prompt, structured_response_schema = response_format
messages = [SystemMessage(content=system_prompt)] + list(messages)
resolved_model = await _aresolve_model(state, runtime)
model_with_structured_output = _get_model(
resolved_model
).with_structured_output(
cast(StructuredResponseSchema, structured_response_schema)
)
response = await model_with_structured_output.ainvoke(messages, config)
return {"structured_response": response}
if not tool_calling_enabled:
# Define a new graph
workflow = StateGraph(state_schema=state_schema, context_schema=context_schema)
workflow.add_node(
"agent",
RunnableCallable(call_model, acall_model),
input_schema=input_schema,
)
if pre_model_hook is not None:
workflow.add_node("pre_model_hook", pre_model_hook) # type: ignore[arg-type]
workflow.add_edge("pre_model_hook", "agent")
entrypoint = "pre_model_hook"
else:
entrypoint = "agent"
workflow.set_entry_point(entrypoint)
if post_model_hook is not None:
workflow.add_node("post_model_hook", post_model_hook) # type: ignore[arg-type]
workflow.add_edge("agent", "post_model_hook")
if response_format is not None:
workflow.add_node(
"generate_structured_response",
RunnableCallable(
generate_structured_response,
agenerate_structured_response,
),
)
if post_model_hook is not None:
workflow.add_edge("post_model_hook", "generate_structured_response")
else:
workflow.add_edge("agent", "generate_structured_response")
return workflow.compile(
checkpointer=checkpointer,
store=store,
interrupt_before=interrupt_before,
interrupt_after=interrupt_after,
debug=debug,
name=name,
)
# Define the function that determines whether to continue or not
def should_continue(state: StateSchema) -> Union[str, list[Send]]:
messages = _get_state_value(state, "messages")
last_message = messages[-1]
# If there is no function call, then we finish
if not isinstance(last_message, AIMessage) or not last_message.tool_calls:
if post_model_hook is not None:
return "post_model_hook"
elif response_format is not None:
return "generate_structured_response"
else:
return END
# Otherwise if there is, we continue
else:
if version == "v1":
return "tools"
elif version == "v2":
if post_model_hook is not None:
return "post_model_hook"
return [
Send(
"tools",
ToolCallWithContext(
__type="tool_call_with_context",
tool_call=tool_call,
state=state,
),
)
for tool_call in last_message.tool_calls
]
# Define a new graph
workflow = StateGraph(
state_schema=state_schema or AgentState, context_schema=context_schema
# Build the graph using the internal builder
builder = _AgentBuilder(
model=model,
tools=tools,
prompt=prompt,
response_format=response_format,
pre_model_hook=pre_model_hook,
post_model_hook=post_model_hook,
state_schema=state_schema,
context_schema=context_schema,
version=version,
name=name,
)
# Define the two nodes we will cycle between
workflow.add_node(
"agent",
RunnableCallable(call_model, acall_model),
input_schema=input_schema,
)
workflow.add_node("tools", tool_node)
workflow = builder.build()
# Optionally add a pre-model hook node that will be called
# every time before the "agent" (LLM-calling node)
if pre_model_hook is not None:
workflow.add_node("pre_model_hook", pre_model_hook) # type: ignore[arg-type]
workflow.add_edge("pre_model_hook", "agent")
entrypoint = "pre_model_hook"
else:
entrypoint = "agent"
# Set the entrypoint as `agent`
# This means that this node is the first one called
workflow.set_entry_point(entrypoint)
agent_paths = []
post_model_hook_paths = [entrypoint, "tools"]
# Add a post model hook node if post_model_hook is provided
if post_model_hook is not None:
workflow.add_node("post_model_hook", post_model_hook) # type: ignore[arg-type]
agent_paths.append("post_model_hook")
workflow.add_edge("agent", "post_model_hook")
else:
agent_paths.append("tools")
# Add a structured output node if response_format is provided
if response_format is not None:
workflow.add_node(
"generate_structured_response",
RunnableCallable(
generate_structured_response,
agenerate_structured_response,
),
)
if post_model_hook is not None:
post_model_hook_paths.append("generate_structured_response")
else:
agent_paths.append("generate_structured_response")
else:
if post_model_hook is not None:
post_model_hook_paths.append(END)
else:
agent_paths.append(END)
if post_model_hook is not None:
def post_model_hook_router(state: StateSchema) -> Union[str, list[Send]]:
"""Route to the next node after post_model_hook.
Routes to one of:
* "tools": if there are pending tool calls without a corresponding message.
* "generate_structured_response": if no pending tool calls exist and response_format is specified.
* END: if no pending tool calls exist and no response_format is specified.
"""
messages = _get_state_value(state, "messages")
tool_messages = [
m.tool_call_id for m in messages if isinstance(m, ToolMessage)
]
last_ai_message = next(
m for m in reversed(messages) if isinstance(m, AIMessage)
)
pending_tool_calls = [
c for c in last_ai_message.tool_calls if c["id"] not in tool_messages
]
if pending_tool_calls:
return [
Send(
"tools",
ToolCallWithContext(
__type="tool_call_with_context",
tool_call=tool_call,
state=state,
),
)
for tool_call in pending_tool_calls
]
elif isinstance(messages[-1], ToolMessage):
return entrypoint
elif response_format is not None:
return "generate_structured_response"
else:
return END
workflow.add_conditional_edges(
"post_model_hook",
post_model_hook_router, # type: ignore[arg-type]
path_map=post_model_hook_paths,
)
workflow.add_conditional_edges(
"agent",
should_continue, # type: ignore[arg-type]
path_map=agent_paths,
)
def route_tool_responses(state: StateSchema) -> str:
for m in reversed(_get_state_value(state, "messages")):
if not isinstance(m, ToolMessage):
break
if m.name in should_return_direct:
return END
# handle a case of parallel tool calls where
# the tool w/ `return_direct` was executed in a different `Send`
if isinstance(m, AIMessage) and m.tool_calls:
if any(call["name"] in should_return_direct for call in m.tool_calls):
return END
return entrypoint
if should_return_direct:
workflow.add_conditional_edges(
"tools", route_tool_responses, path_map=[entrypoint, END]
)
else:
workflow.add_edge("tools", entrypoint)
# Finally, we compile it!
# This compiles it into a LangChain Runnable,
# meaning you can use it as you would any other runnable
# Compile and return the graph
return workflow.compile(
checkpointer=checkpointer,
store=store,
+1 -374
View File
@@ -13,12 +13,10 @@ from typing import (
)
import pytest
from langchain_core.language_models import BaseChatModel
from langchain_core.messages import (
AIMessage,
AnyMessage,
HumanMessage,
MessageLikeRepresentation,
RemoveMessage,
SystemMessage,
ToolCall,
@@ -54,7 +52,6 @@ from langgraph.prebuilt.tool_node import (
_get_state_args,
_infer_handled_types,
)
from langgraph.runtime import Runtime
from langgraph.store.base import BaseStore
from langgraph.store.memory import InMemoryStore
from langgraph.types import Command, Interrupt, interrupt
@@ -1095,7 +1092,7 @@ def test_inspect_react() -> None:
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_react_with_subgraph_tools(
sync_checkpointer: BaseCheckpointSaver, version: Literal["v1", "v2"]
sync_checkpointer: BaseCheckpointSaver, version: str
) -> None:
class State(TypedDict):
a: int
@@ -1370,376 +1367,6 @@ def test_get_model() -> None:
_get_model(RunnableLambda(lambda message: message))
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_basic(version: str) -> None:
"""Test basic dynamic model functionality."""
def dynamic_model(state, runtime: Runtime):
# Return different models based on state
if "urgent" in state["messages"][-1].content:
return FakeToolCallingModel(tool_calls=[])
else:
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(dynamic_model, [], version=version)
result = agent.invoke({"messages": [HumanMessage("hello")]})
assert len(result["messages"]) == 2
assert result["messages"][-1].content == "hello"
result = agent.invoke({"messages": [HumanMessage("urgent help")]})
assert len(result["messages"]) == 2
assert result["messages"][-1].content == "urgent help"
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_with_tools(version: Literal["v1", "v2"]) -> None:
"""Test dynamic model with tool calling."""
@dec_tool
def basic_tool(x: int) -> str:
"""Basic tool."""
return f"basic: {x}"
@dec_tool
def advanced_tool(x: int) -> str:
"""Advanced tool."""
return f"advanced: {x}"
def dynamic_model(state: dict, runtime: Runtime) -> BaseChatModel:
# Return model with different behaviors based on message content
if "advanced" in state["messages"][-1].content:
return FakeToolCallingModel(
tool_calls=[
[{"args": {"x": 1}, "id": "1", "name": "advanced_tool"}],
[],
]
)
else:
return FakeToolCallingModel(
tool_calls=[[{"args": {"x": 1}, "id": "1", "name": "basic_tool"}], []]
)
agent = create_react_agent(
dynamic_model, [basic_tool, advanced_tool], version=version
)
# Test basic tool usage
result = agent.invoke({"messages": [HumanMessage("basic request")]})
assert len(result["messages"]) == 3
tool_message = result["messages"][-1]
assert tool_message.content == "basic: 1"
assert tool_message.name == "basic_tool"
# Test advanced tool usage
result = agent.invoke({"messages": [HumanMessage("advanced request")]})
assert len(result["messages"]) == 3
tool_message = result["messages"][-1]
assert tool_message.content == "advanced: 1"
assert tool_message.name == "advanced_tool"
@dataclasses.dataclass
class Context:
user_id: str
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_with_context(version: str) -> None:
"""Test dynamic model using config parameters."""
def dynamic_model(state, runtime: Runtime[Context]):
# Use context to determine model behavior
user_id = runtime.context.user_id
if user_id == "user_premium":
return FakeToolCallingModel(tool_calls=[])
else:
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(
dynamic_model, [], context_schema=Context, version=version
)
# Test with basic user
result = agent.invoke(
{"messages": [HumanMessage("hello")]},
context=Context(user_id="user_basic"),
)
assert len(result["messages"]) == 2
# Test with premium user
result = agent.invoke(
{"messages": [HumanMessage("hello")]},
context=Context(user_id="user_premium"),
)
assert len(result["messages"]) == 2
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_with_state_schema(version: Literal["v1", "v2"]) -> None:
"""Test dynamic model with custom state schema."""
class CustomDynamicState(AgentState):
model_preference: str = "default"
def dynamic_model(state: CustomDynamicState, runtime: Runtime) -> BaseChatModel:
# Use custom state field to determine model
if state.get("model_preference") == "advanced":
return FakeToolCallingModel(tool_calls=[])
else:
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(
dynamic_model, [], state_schema=CustomDynamicState, version=version
)
result = agent.invoke(
{"messages": [HumanMessage("hello")], "model_preference": "advanced"}
)
assert len(result["messages"]) == 2
assert result["model_preference"] == "advanced"
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_with_prompt(version: Literal["v1", "v2"]) -> None:
"""Test dynamic model with different prompt types."""
def dynamic_model(state: AgentState, runtime: Runtime) -> BaseChatModel:
return FakeToolCallingModel(tool_calls=[])
# Test with string prompt
agent = create_react_agent(dynamic_model, [], prompt="system_msg", version=version)
result = agent.invoke({"messages": [HumanMessage("human_msg")]})
assert result["messages"][-1].content == "system_msg-human_msg"
# Test with callable prompt
def dynamic_prompt(state: AgentState) -> list[MessageLikeRepresentation]:
"""Generate a dynamic system message based on state."""
return [{"role": "system", "content": "system_msg"}] + list(state["messages"])
agent = create_react_agent(
dynamic_model, [], prompt=dynamic_prompt, version=version
)
result = agent.invoke({"messages": [HumanMessage("human_msg")]})
assert result["messages"][-1].content == "system_msg-human_msg"
async def test_dynamic_model_async() -> None:
"""Test dynamic model with async operations."""
def dynamic_model(state: AgentState, runtime: Runtime) -> BaseChatModel:
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(dynamic_model, [])
result = await agent.ainvoke({"messages": [HumanMessage("hello async")]})
assert len(result["messages"]) == 2
assert result["messages"][-1].content == "hello async"
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_with_structured_response(version: str) -> None:
"""Test dynamic model with structured response format."""
class TestResponse(BaseModel):
message: str
confidence: float
def dynamic_model(state, runtime: Runtime):
expected_response = TestResponse(message="dynamic response", confidence=0.9)
return FakeToolCallingModel(
tool_calls=[], structured_response=expected_response
)
agent = create_react_agent(
dynamic_model, [], response_format=TestResponse, version=version
)
result = agent.invoke({"messages": [HumanMessage("hello")]})
assert "structured_response" in result
assert result["structured_response"].message == "dynamic response"
assert result["structured_response"].confidence == 0.9
def test_dynamic_model_with_checkpointer(sync_checkpointer):
"""Test dynamic model with checkpointer."""
call_count = 0
def dynamic_model(state: AgentState, runtime: Runtime) -> BaseChatModel:
nonlocal call_count
call_count += 1
return FakeToolCallingModel(
tool_calls=[],
# Incrementing the call count as it is used to assign an id
# to the AIMessage.
# The default reducer semantics are to overwrite an existing message
# with the new one if the id matches.
index=call_count,
)
agent = create_react_agent(dynamic_model, [], checkpointer=sync_checkpointer)
config = {"configurable": {"thread_id": "test_dynamic"}}
# First call
result1 = agent.invoke({"messages": [HumanMessage("hello")]}, config)
assert len(result1["messages"]) == 2 # Human + AI message
# Second call - should load from checkpoint
result2 = agent.invoke({"messages": [HumanMessage("world")]}, config)
assert len(result2["messages"]) == 4
# Dynamic model should be called each time
assert call_count >= 2
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_state_dependent_tools(version: Literal["v1", "v2"]) -> None:
"""Test dynamic model that changes available tools based on state."""
@dec_tool
def tool_a(x: int) -> str:
"""Tool A."""
return f"A: {x}"
@dec_tool
def tool_b(x: int) -> str:
"""Tool B."""
return f"B: {x}"
def dynamic_model(state, runtime: Runtime):
# Switch tools based on message history
if any("use_b" in msg.content for msg in state["messages"]):
return FakeToolCallingModel(
tool_calls=[[{"args": {"x": 2}, "id": "1", "name": "tool_b"}], []]
)
else:
return FakeToolCallingModel(
tool_calls=[[{"args": {"x": 1}, "id": "1", "name": "tool_a"}], []]
)
agent = create_react_agent(dynamic_model, [tool_a, tool_b], version=version)
# Ask to use tool B
result = agent.invoke({"messages": [HumanMessage("use_b please")]})
last_message = result["messages"][-1]
assert isinstance(last_message, ToolMessage)
assert last_message.content == "B: 2"
# Ask to use tool A
result = agent.invoke({"messages": [HumanMessage("hello")]})
last_message = result["messages"][-1]
assert isinstance(last_message, ToolMessage)
assert last_message.content == "A: 1"
@pytest.mark.parametrize("version", REACT_TOOL_CALL_VERSIONS)
def test_dynamic_model_error_handling(version: Literal["v1", "v2"]) -> None:
"""Test error handling in dynamic model."""
def failing_dynamic_model(state, runtime: Runtime):
if "fail" in state["messages"][-1].content:
raise ValueError("Dynamic model failed")
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(failing_dynamic_model, [], version=version)
# Normal operation should work
result = agent.invoke({"messages": [HumanMessage("hello")]})
assert len(result["messages"]) == 2
# Should propagate the error
with pytest.raises(ValueError, match="Dynamic model failed"):
agent.invoke({"messages": [HumanMessage("fail now")]})
def test_dynamic_model_vs_static_model_behavior():
"""Test that dynamic and static models produce equivalent results when configured the same."""
# Static model
static_model = FakeToolCallingModel(tool_calls=[])
static_agent = create_react_agent(static_model, [])
# Dynamic model returning the same model
def dynamic_model(state, runtime: Runtime):
return FakeToolCallingModel(tool_calls=[])
dynamic_agent = create_react_agent(dynamic_model, [])
input_msg = {"messages": [HumanMessage("test message")]}
static_result = static_agent.invoke(input_msg)
dynamic_result = dynamic_agent.invoke(input_msg)
# Results should be equivalent (content-wise, IDs may differ)
assert len(static_result["messages"]) == len(dynamic_result["messages"])
assert static_result["messages"][0].content == dynamic_result["messages"][0].content
assert static_result["messages"][1].content == dynamic_result["messages"][1].content
def test_dynamic_model_receives_correct_state():
"""Test that the dynamic model function receives the correct state, not the model input."""
received_states = []
class CustomAgentState(AgentState):
custom_field: str
def dynamic_model(state, runtime: Runtime) -> BaseChatModel:
# Capture the state that's passed to the dynamic model function
received_states.append(state)
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(dynamic_model, [], state_schema=CustomAgentState)
# Test with initial state
input_state = {"messages": [HumanMessage("hello")], "custom_field": "test_value"}
agent.invoke(input_state)
# The dynamic model function should receive the original state, not the processed model input
assert len(received_states) == 1
received_state = received_states[0]
# Should have the custom field from original state
assert "custom_field" in received_state
assert received_state["custom_field"] == "test_value"
# Should have the original messages
assert len(received_state["messages"]) == 1
assert received_state["messages"][0].content == "hello"
async def test_dynamic_model_receives_correct_state_async():
"""Test that the async dynamic model function receives the correct state, not the model input."""
received_states = []
class CustomAgentStateAsync(AgentState):
custom_field: str
def dynamic_model(state, runtime: Runtime):
# Capture the state that's passed to the dynamic model function
received_states.append(state)
return FakeToolCallingModel(tool_calls=[])
agent = create_react_agent(dynamic_model, [], state_schema=CustomAgentStateAsync)
# Test with initial state
input_state = {
"messages": [HumanMessage("hello async")],
"custom_field": "test_value_async",
}
await agent.ainvoke(input_state)
# The dynamic model function should receive the original state, not the processed model input
assert len(received_states) == 1
received_state = received_states[0]
# Should have the custom field from original state
assert "custom_field" in received_state
assert received_state["custom_field"] == "test_value_async"
# Should have the original messages
assert len(received_state["messages"]) == 1
assert received_state["messages"][0].content == "hello async"
def test_pre_model_hook() -> None:
model = FakeToolCallingModel(tool_calls=[])
+2 -2
View File
@@ -316,7 +316,7 @@ wheels = [
[[package]]
name = "langgraph"
version = "0.6.0"
version = "0.6.0a1"
source = { editable = "../langgraph" }
dependencies = [
{ name = "langchain-core" },
@@ -430,7 +430,7 @@ dev = [
[[package]]
name = "langgraph-checkpoint-sqlite"
version = "2.0.11"
version = "2.0.10"
source = { editable = "../checkpoint-sqlite" }
dependencies = [
{ name = "aiosqlite" },