langgraph[patch]: fix create_react_agent inspectability (#2948)

Co-authored-by: vbarda <vadym@langchain.dev>

libs/langgraph/langgraph/prebuilt/chat_agent_executor.py

@@ -554,6 +554,10 @@ def create_react_agent(
     )
     model_runnable = preprocessor | model
 
+    # 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}
+
     # Define the function that calls the model
     def call_model(state: AgentState, config: RunnableConfig) -> AgentState:
         _validate_chat_history(state["messages"])
@@ -673,10 +677,6 @@ def create_react_agent(
         should_continue,
     )
 
-    # 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 route_tool_responses(state: AgentState) -> Literal["agent", "__end__"]:
         for m in reversed(state["messages"]):
             if not isinstance(m, ToolMessage):

libs/langgraph/tests/test_prebuilt.py

@@ -1,4 +1,5 @@
 import dataclasses
+import inspect
 import json
 from functools import partial
 from typing import (
@@ -2040,3 +2041,9 @@ def test__get_state_args() -> None:
         return 0.0
 
     assert _get_state_args(foo) == {"a": None, "b": "bar"}
+
+
+def test_inspect_react() -> None:
+    model = FakeToolCallingModel(tool_calls=[])
+    agent = create_react_agent(model, [])
+    inspect.getclosurevars(agent.nodes["agent"].bound.func)