diff --git a/python/valuecell/core/coordinate/orchestrator.py b/python/valuecell/core/coordinate/orchestrator.py
index 85e218d79..2c2b78635 100644
--- a/python/valuecell/core/coordinate/orchestrator.py
+++ b/python/valuecell/core/coordinate/orchestrator.py
@@ -216,7 +216,6 @@ async def close_session(self, session_id: str):
             session_id,
             Role.SYSTEM,
             f"Session closed. {cancelled_count} tasks were cancelled.",
-            agent_name="orchestrator",
         )
 
     async def get_session_history(self, session_id: str):
@@ -289,6 +288,9 @@ async def _handle_new_request(
         """Handle a new user request"""
         session_id = user_input.meta.session_id
         thread_id = generate_thread_id()
+        yield self._response_factory.thread_started(
+            conversation_id=session_id, thread_id=thread_id
+        )
 
         # Add user message to session
         await self.session_manager.add_message(
@@ -384,6 +386,9 @@ async def _continue_planning(
         original_user_input = context.get_metadata("original_user_input")
         thread_id = generate_thread_id()
         context.thread_id = thread_id
+        yield self._response_factory.thread_started(
+            conversation_id=session_id, thread_id=thread_id
+        )
 
         if not all([planning_task, original_user_input]):
             yield self._response_factory.plan_failed(
@@ -508,7 +513,6 @@ async def _execute_plan_with_input_support(
                                 session_id,
                                 Role.AGENT,
                                 agent_responses[task.agent_name],
-                                agent_name=task.agent_name,
                             )
                             agent_responses[task.agent_name] = ""
 
@@ -614,7 +618,7 @@ async def _save_remaining_responses(self, session_id: str, agent_responses: dict
         for agent_name, full_response in agent_responses.items():
             if full_response.strip():
                 await self.session_manager.add_message(
-                    session_id, Role.AGENT, full_response, agent_name=agent_name
+                    session_id, Role.AGENT, full_response
                 )
 
 
diff --git a/python/valuecell/core/coordinate/response.py b/python/valuecell/core/coordinate/response.py
index 399af08c2..ab9f73190 100644
--- a/python/valuecell/core/coordinate/response.py
+++ b/python/valuecell/core/coordinate/response.py
@@ -16,6 +16,7 @@
     SystemFailedResponse,
     TaskCompletedResponse,
     TaskFailedResponse,
+    ThreadStartedResponse,
     ToolCallPayload,
     ToolCallResponse,
     UnifiedResponseData,
@@ -28,6 +29,15 @@ def conversation_started(self, conversation_id: str) -> ConversationStartedRespo
             data=UnifiedResponseData(conversation_id=conversation_id)
         )
 
+    def thread_started(
+        self, conversation_id: str, thread_id: str
+    ) -> ThreadStartedResponse:
+        return ThreadStartedResponse(
+            data=UnifiedResponseData(
+                conversation_id=conversation_id, thread_id=thread_id
+            )
+        )
+
     def system_failed(self, conversation_id: str, content: str) -> SystemFailedResponse:
         return SystemFailedResponse(
             data=UnifiedResponseData(
diff --git a/python/valuecell/core/coordinate/tests/test_orchestrator.py b/python/valuecell/core/coordinate/tests/test_orchestrator.py
index 30caa4bbd..ff5e711ce 100644
--- a/python/valuecell/core/coordinate/tests/test_orchestrator.py
+++ b/python/valuecell/core/coordinate/tests/test_orchestrator.py
@@ -308,9 +308,9 @@ async def test_planner_error(
     async for chunk in orchestrator.process_user_input(sample_user_input):
         out.append(chunk)
 
-    assert len(out) == 1
-    assert "(Error)" in out[0].data.payload.content
-    assert "Planning failed" in out[0].data.payload.content
+    assert len(out) == 2
+    assert "(Error)" in out[1].data.payload.content
+    assert "Planning failed" in out[1].data.payload.content
 
 
 @pytest.mark.asyncio
@@ -328,7 +328,7 @@ async def test_agent_connection_error(
     async for chunk in orchestrator.process_user_input(sample_user_input):
         out.append(chunk)
 
-    assert any("(Error)" in c.data.payload.content for c in out)
+    assert any("(Error)" in c.data.payload.content for c in out if c.data.payload)
 
 
 @pytest.mark.asyncio
diff --git a/python/valuecell/core/types.py b/python/valuecell/core/types.py
index 89a640adc..ab06e2dc5 100644
--- a/python/valuecell/core/types.py
+++ b/python/valuecell/core/types.py
@@ -49,6 +49,7 @@ def clear_desired_agent(self) -> None:
 
 class SystemResponseEvent(str, Enum):
     CONVERSATION_STARTED = "conversation_started"
+    THREAD_STARTED = "thread_started"
     PLAN_REQUIRE_USER_INPUT = "plan_require_user_input"
     PLAN_FAILED = "plan_failed"
     TASK_FAILED = "task_failed"
@@ -172,6 +173,13 @@ class ConversationStartedResponse(BaseResponse):
     )
 
 
+class ThreadStartedResponse(BaseResponse):
+    event: Literal[SystemResponseEvent.THREAD_STARTED] = Field(
+        SystemResponseEvent.THREAD_STARTED,
+        description="The event type of the response",
+    )
+
+
 class PlanRequireUserInputResponse(BaseResponse):
     event: Literal[SystemResponseEvent.PLAN_REQUIRE_USER_INPUT] = Field(
         SystemResponseEvent.PLAN_REQUIRE_USER_INPUT,