Commit Graph
25 Commits
Author SHA1 Message Date
4571b708d9 fix(langgraph): support emitting messages from subgraphs when messages mode explicitly requested (#5836)
Reproduces:
https://github.com/langchain-ai/langgraph/issues/5249#issuecomment-3156519635
Caused after this change:
https://github.com/langchain-ai/langgraph/pull/4843

Fix to allow emitting messages from subgraphs if the subgraphs
explicitly used a stream mode "messages".

```python

def node_in_parent(...):
   # subgraph was called as a function.
   # messages are explicitly requested.
   for event in subgraph.stream(..., stream_mode="messages"):
      # something is done with `event`
   return ...

# subgraphs = False!
parent_graph.invoke(..., subgraphs=False)
```

The code above should continue to work correctly regardless of the value
of subgraphs as streaming messages was requested explicitly in the
parent node!

---------

Co-authored-by: Sydney Runkle <54324534+sydney-runkle@users.noreply.github.com>
2025-08-07 10:10:52 -04:00
f6aa19709e feat(prebuilt): Add dynamic model to create_react_agent (#5651)
This PR allows a developer to change the model configuration at run time based on context. This includes that list of tools available to the model to call.

```python
def create_react_agent(
    model: Union[
        str, 
	LanguageModelLike,
        Callable[[SateLike, Runtime...], BaseChatModel], # <--- New
    ],
    tools: Union[
      Sequence[Union[BaseTool, Callable, dict[str, Any]]], ToolNode]
    ],
    *,
....


llm = init_chat_model(...)

def prepare_model(state, runtime):
   selected_tool_names = func(state, context)
   return llm.bind(tools=selected_tool_names)

create_react_agent(
  prepare_model,
  tools=all_known_tools
)
```

## Semantics

1. `tools` = are the known tools, used to configure ToolNode and will
configure:
    1. model provided as string
    2. model provided as BaseChatModel (if it has no tools bound to it)
2. If a user provides a dynamic model (callable), the user is
responsible for binding tools


Alternative considered:

1. Passing `Callable[[SateLike, Config...], list[BaseTool]]` to tools
2. Passing `Callable[[SateLike, Config...], list[str]]` to a tool
selector

Both have the issue that there's non obvious interplay between tool
selection and dynamic models. (i.e., if we want to introduce dynamic
models at in the future, the API will become tricky to explain)

---------

Co-authored-by: Sydney Runkle <54324534+sydney-runkle@users.noreply.github.com>
2025-07-25 14:48:15 -04:00
Sydney RunkleandGitHub 90ba4c5205 Merge branch 'main' into v1 2025-07-21 10:06:23 -04:00
Eugene YurtsevandGitHub f63bec8578 chore(prebuilt): restructure tool node and tool injection logic (#5562)
* Cleaning up the underlying tool injection logic which is happening in
multiple locations.
* State was being injected into the ToolCall via Send in two places in
create react agent and the logic doesn't belong there, the actual
injection should be happening inside the ToolNode where there's
awareness of what run time parameters the tool accepts.

Change is required to unblock:
https://github.com/langchain-ai/langgraph/pull/5537
2025-07-18 09:59:14 -04:00
Sydney RunkleandGitHub d1710e2eac change[langgraph]: clean up Interrupt interface for v1 (#5405) 2025-07-09 14:03:08 -04:00
Sydney RunkleandGitHub 8c4e698c5a langgraph[change]: solidify public/private differentiations (#5252)
* public interfaces for channels
* public interfaces for func
* public interfaces for graph
* pi for managed
* first pass public interface for top level modules
* first pass at private for utils -> _internal
* private interface for pregel
* scratchpad/stream protocol move
* docs update
* backwards compat for runnable
* deprecation warning for send and interrupt
* deprecation for pregel import
2025-07-02 16:48:53 -04:00
William FHandGitHub 7fda427601 fix: [prebuilt] Checks for pre-bound model with builtin tools (#5203) 2025-06-26 01:34:21 +00:00
Nuno Campos a1c856c088 Reduce extraneous keys in checkpoint.metadata
- Leave it up to each checkpointer implementation to decide whether to merge in configurable/metadata (previously PregelLoop would do some of this always)
- Never copy over internal langgraph keys into checkpoint.metadata (these are redundant/misleading to include)
2025-06-17 17:40:18 -07:00
Sydney RunkleandGitHub 0171e9a323 fix(langgraph): remove deprecated output usage in favor of output_schema (#5095)
use output_schema
2025-06-13 12:34:39 -04:00
Nuno CamposandGitHub 76661f4c9c Remove Checkpoint.writes (#4822) 2025-05-28 14:04:45 -07:00
Nuno CamposandGitHub c32677c92d Remove old checkpoint test fixtures (#4814) 2025-05-28 14:03:12 -07:00
Sydney RunkleandGitHub 19ca6b416b fix: post_model_hook should inject state + store into tool calls if necessary (#4842) 2025-05-27 17:42:20 +00:00
Nuno Campos 936176eb21 Remove Checkpoint.writes
- This has been superseded by saving the individual writes of each task through put_writes()
- Removing this speeds up checkpoint operations as it was duplicating data saved elsewhere already
2025-05-25 19:06:46 -07:00
Nuno Campos bc17c3522b Remove old checkpoint test fixtures
- Now all tests fully migrated to more recent sync_checkpointer and async_checkpointer fixtures for parametrising on checkpointer
- Use sync/async_store fixtures where tests used only in memory store
- Remove unused "should snapshot" check for older versions of langchain core no longer tested against
2025-05-24 14:27:13 -07:00
Sydney RunkleandGitHub 7bd8616b1e feature: Implement post_model_hook and HumanInterruptNode (#4583) 2025-05-19 14:07:42 -04:00
Sydney RunkleandGitHub 228a08b966 ci: migrate to uv! (#4698)
* Migrate to `uv`
* Format `pyproject.toml` files properly
* Remove upper bounds on dependencies, and bounds on dev dependencies
(we should be using latest)
* Move to hatch for packaing

In the future we should:
* Set up dependabot / automate lockfile updates and tests
* Add tests for min compatible versions (I'll do this right after merge)
* Use dynamic versioning
* Bump `pydantic` to v2.11.4 in the lockfile, we have some tests failing
2025-05-15 17:39:14 -07:00
Nuno CamposandGitHub 909a4591a8 Port checkpointer/store fixtures in langgraph-prebuilt to idiomatic pattern (#4629) 2025-05-09 19:42:44 +00:00
Vadym BardaandGitHub 0e61cc2cf6 prebuilt: remove state_modifier (#4439)
Removes support for `state_modifier` param in `create_react_agent`. To
specify system prompt / instructions use `prompt` parameter.
2025-05-05 09:49:28 -04:00
vbarda 4b7ec256e9 prebuilt: switch to executing parallel tool calls via Send by default 2025-04-28 11:07:27 -04:00
Sydney Runkle 9e89b68596 fixing prebuilt tests 2025-04-22 17:24:54 -07:00
Vadym BardaandGitHub 67e8f8fc11 prebuilt: add optional pre-model hook that runs before calling LLM in create_react_agent (#4059)
Example:

```python
from typing import Any
from langchain_openai import ChatOpenAI
from langchain_community.tools.tavily_search import TavilySearchResults
from langchain_core.messages import AnyMessage
from langchain_core.messages.utils import count_tokens_approximately

from langgraph.graph import MessagesState
from langgraph.prebuilt.chat_agent_executor import create_react_agent, AgentState
from langgraph.checkpoint.memory import InMemorySaver

from langmem.short_term import SummarizationNode, RunningSummary


class State(MessagesState):
    context: dict[str, Any]

search = TavilySearchResults(max_results=3)
tools = [search]

model = ChatOpenAI(model="gpt-4o")
summarization_model = model.bind(max_tokens=256)

summarization_node = SummarizationNode(
    token_counter=count_tokens_approximately,
    model=summarization_model,
    max_tokens=2048,
    max_summary_tokens=256,
    output_messages_key="messages"
    # output_messages_key="llm_input_messages"
)

checkpointer = InMemorySaver()


class State(AgentState):
    user_language: str

    # summarization-related keys
    context: dict[str, Any]


def prompt(state):
    language = state["user_language"]
    system_msg = f"Always respond in {language}"
    return [{"role": "system", "content": system_msg}] + state["messages"]


graph = create_react_agent(
    model,
    tools,
    prompt=prompt,
    pre_model_hook=summarization_node,
    state_schema=State,
    checkpointer=checkpointer
)
```
2025-04-02 15:41:31 +00:00
Nuno Campos 49bb08a3f9 Update prebuilt test 2025-03-27 17:58:29 -07:00
3183146141 prebuilt: allow pydantic model as state schema in create_react_agent (#3559)
Inherited attributes where not considered.
Pydantic model can inherit from other pydantic models. In those cases,
inherited attributes where not considered in the check and the code
fails.

---------

Co-authored-by: vbarda <vadym@langchain.dev>
2025-03-07 16:49:51 -05:00
Vadym BardaandGitHub e8dd682320 prebuilt: allow passing RunnableSequence as a model (#3706) 2025-03-06 02:37:55 +00:00
Vadym BardaandGitHub 24c13c211e langgraph: separate prebuilt into a standalone package (#3589) 2025-02-26 18:33:07 -05:00