cr

libs/prebuilt/langgraph/prebuilt/tool_node.py

@@ -347,6 +347,23 @@ class ToolCallRequestMismatchError(ValueError):
     """`tool_call["name"]` and `tool` disagree on a `ToolCallRequest`."""
 
 
+def _check_not_redirected_without_tool(
+    request: ToolCallRequest, original_name: str, original_tool: BaseTool | None
+) -> None:
+    """Raise if an interceptor renamed the call but left `tool` as the resolved one."""
+    if (
+        original_tool is not None
+        and request.tool is original_tool
+        and request.tool_call["name"] != original_name
+    ):
+        msg = (
+            f"Interceptor set tool_call name to {request.tool_call['name']!r} but left "
+            f"`tool` as {original_tool.name!r}. Redirecting a call requires setting both; "
+            f"resolve the replacement from `ToolCallRequest.available_tools`."
+        )
+        raise ToolCallRequestMismatchError(msg)
+
+
 class ToolInvocationError(ToolException):
     """An error occurred while invoking a tool due to invalid arguments.
 
@@ -1062,17 +1079,7 @@ class ToolNode(RunnableCallable):
 
         def execute(req: ToolCallRequest) -> ToolMessage | Command:
             """Execute tool with given request. Can be called multiple times."""
-            if (
-                original_tool is not None
-                and req.tool is original_tool
-                and req.tool_call["name"] != original_name
-            ):
-                msg = (
-                    f"Interceptor set tool_call name to {req.tool_call['name']!r} but left "
-                    f"`tool` as {original_tool.name!r}. Redirecting a call requires setting "
-                    f"both; resolve the replacement from `ToolCallRequest.available_tools`."
-                )
-                raise ToolCallRequestMismatchError(msg)
+            _check_not_redirected_without_tool(req, original_name, original_tool)
             return self._execute_tool_sync(req, input_type, config)
 
         # Call wrapper with request and execute callable
@@ -1225,21 +1232,12 @@ class ToolNode(RunnableCallable):
 
         async def execute(req: ToolCallRequest) -> ToolMessage | Command:
             """Execute tool with given request. Can be called multiple times."""
-            if (
-                original_tool is not None
-                and req.tool is original_tool
-                and req.tool_call["name"] != original_name
-            ):
-                msg = (
-                    f"Interceptor set tool_call name to {req.tool_call['name']!r} but left "
-                    f"`tool` as {original_tool.name!r}. Redirecting a call requires setting "
-                    f"both; resolve the replacement from `ToolCallRequest.available_tools`."
-                )
-                raise ToolCallRequestMismatchError(msg)
+            _check_not_redirected_without_tool(req, original_name, original_tool)
             return await self._execute_tool_async(req, input_type, config)
 
         def _sync_execute(req: ToolCallRequest) -> ToolMessage | Command:
             """Sync execute fallback for sync wrapper."""
+            _check_not_redirected_without_tool(req, original_name, original_tool)
             return self._execute_tool_sync(req, input_type, config)
 
         # Call wrapper with request and execute callable

libs/prebuilt/tests/test_on_tool_call.py

@@ -1499,7 +1499,12 @@ async def test_interceptor_can_redirect_to_another_tool() -> None:
             AIMessage(
                 "",
                 tool_calls=[
-                    {"name": "add", "args": {"a": 5, "b": 3}, "id": "1", "type": "tool_call"}
+                    {
+                        "name": "add",
+                        "args": {"a": 5, "b": 3},
+                        "id": "1",
+                        "type": "tool_call",
+                    }
                 ],
             )
         ],
@@ -1517,7 +1522,9 @@ def test_interceptor_tool_call_name_and_tool_must_agree() -> None:
         request: ToolCallRequest,
         execute: Callable[[ToolCallRequest], ToolMessage | Command],
     ) -> ToolMessage | Command:
-        return execute(request.override(tool_call={**request.tool_call, "name": "other"}))
+        return execute(
+            request.override(tool_call={**request.tool_call, "name": "other"})
+        )
 
     @tool
     def other(a: int, b: int) -> int:
@@ -1532,7 +1539,49 @@ def test_interceptor_tool_call_name_and_tool_must_agree() -> None:
                 AIMessage(
                     "",
                     tool_calls=[
-                        {"name": "add", "args": {"a": 1, "b": 2}, "id": "1", "type": "tool_call"}
+                        {
+                            "name": "add",
+                            "args": {"a": 1, "b": 2},
+                            "id": "1",
+                            "type": "tool_call",
+                        }
+                    ],
+                )
+            ],
+            _create_config_with_runtime(),
+        )
+
+
+async def test_sync_interceptor_under_ainvoke_also_validates_redirect() -> None:
+    """The sync-wrapper fallback used by `ainvoke` must validate too, not just `invoke`."""
+
+    def rename_only(
+        request: ToolCallRequest,
+        execute: Callable[[ToolCallRequest], ToolMessage | Command],
+    ) -> ToolMessage | Command:
+        return execute(
+            request.override(tool_call={**request.tool_call, "name": "other"})
+        )
+
+    @tool
+    def other(a: int, b: int) -> int:
+        """Another tool."""
+        return 0
+
+    # Only a sync wrapper is configured, so `ainvoke` routes through `_sync_execute`.
+    node = ToolNode([add, other], wrap_tool_call=rename_only)
+    with pytest.raises(ToolCallRequestMismatchError, match="other"):
+        await node.ainvoke(
+            [
+                AIMessage(
+                    "",
+                    tool_calls=[
+                        {
+                            "name": "add",
+                            "args": {"a": 1, "b": 2},
+                            "id": "1",
+                            "type": "tool_call",
+                        }
                     ],
                 )
             ],