Fix/langgraph concurrent requests and tool name none

integrations/langgraph/python/ag_ui_langgraph/agent.py

@@ -109,6 +109,14 @@ def __init__(self, *, name: str, graph: CompiledStateGraph, description: Optiona
         self.active_run: Optional[RunMetadata] = None
         self.constant_schema_keys = ['messages', 'tools']
 
+    def clone(self) -> "LangGraphAgent":
+        return LangGraphAgent(
+            name=self.name,
+            graph=self.graph,
+            description=self.description,
+            config=self.config,
+        )
+
     def _dispatch_event(self, event: ProcessedEvents) -> str:
         if event.type == EventType.RAW:
             event.event = make_json_safe(event.event)
@@ -896,7 +904,7 @@ async def _handle_single_event(self, event: Any, state: State) -> AsyncGenerator
                             ToolCallStartEvent(
                                 type=EventType.TOOL_CALL_START,
                                 tool_call_id=tool_msg.tool_call_id,
-                                tool_call_name=tool_msg.name,
+                                tool_call_name=tool_msg.name or event.get("name", ""),
                                 parent_message_id=tool_msg.id,
                                 raw_event=event,
                             )

integrations/langgraph/python/ag_ui_langgraph/endpoint.py

@@ -17,8 +17,13 @@ async def langgraph_agent_endpoint(input_data: RunAgentInput, request: Request):
         # Create an event encoder to properly format SSE events
         encoder = EventEncoder(accept=accept_header)
 
+        # Clone the agent so each request gets its own isolated state.
+        # LangGraphAgent stores per-request state in self.active_run; sharing a
+        # single instance across concurrent requests corrupts that state.
+        request_agent = agent.clone()
+
         async def event_generator():
-            async for event in agent.run(input_data):
+            async for event in request_agent.run(input_data):
                 yield encoder.encode(event)
 
         return StreamingResponse(