fix(runtime): skip hidden human messages in journal (#3698)

Co-authored-by: rayhpeng <rayhpeng@gmail.com>

backend/packages/harness/deerflow/runtime/journal.py

@@ -225,7 +225,7 @@ class RunJournal(BaseCallbackHandler):
         if not self._first_human_msg and messages:
             for batch in reversed(messages):
                 for m in reversed(batch):
-                    if isinstance(m, HumanMessage) and m.name != "summary":
+                    if isinstance(m, HumanMessage) and m.name != "summary" and m.additional_kwargs.get("hide_from_ui") is not True:
                         caller = self._identify_caller(tags)
                         self.set_first_human_message(m.text)
                         self._put(

backend/tests/test_run_journal.py

@@ -854,6 +854,76 @@ class TestChatModelStartHumanMessage:
 
         assert j._first_human_msg == "Real question"
 
+    @pytest.mark.anyio
+    async def test_skips_hidden_human_messages(self, journal_setup):
+        """HumanMessages hidden from the UI are internal context, not user input."""
+        from langchain_core.messages import HumanMessage
+
+        j, store = journal_setup
+        messages_batch = [
+            [
+                HumanMessage(content="What is the weather today?"),
+                HumanMessage(
+                    content="Your todo list from earlier...",
+                    name="todo_reminder",
+                    additional_kwargs={"hide_from_ui": True},
+                ),
+            ],
+        ]
+        j.on_chat_model_start({}, messages_batch, run_id=uuid4(), tags=["lead_agent"])
+        await j.flush()
+
+        assert j._first_human_msg == "What is the weather today?"
+        assert j.get_completion_data()["message_count"] == 1
+        events = await store.list_events("t1", "r1")
+        human_events = [e for e in events if e["event_type"] == "llm.human.input"]
+        assert len(human_events) == 1
+        assert human_events[0]["content"]["content"] == "What is the weather today?"
+
+    @pytest.mark.anyio
+    async def test_only_hidden_human_messages_are_not_captured(self, journal_setup):
+        """A prompt containing only internal HumanMessages has no user input."""
+        from langchain_core.messages import HumanMessage
+
+        j, store = journal_setup
+        hidden_message = HumanMessage(
+            content="Internal context",
+            additional_kwargs={"hide_from_ui": True},
+        )
+        j.on_chat_model_start({}, [[hidden_message]], run_id=uuid4(), tags=["lead_agent"])
+        await j.flush()
+
+        assert j._first_human_msg is None
+        assert j.get_completion_data()["message_count"] == 0
+        events = await store.list_events("t1", "r1")
+        assert not any(e["event_type"] == "llm.human.input" for e in events)
+
+    @pytest.mark.anyio
+    async def test_visible_human_message_after_hidden_only_prompt_is_captured(self, journal_setup):
+        """Skipping an internal-only prompt does not block later user input."""
+        from langchain_core.messages import HumanMessage
+
+        j, store = journal_setup
+        hidden_message = HumanMessage(
+            content="Internal context",
+            additional_kwargs={"hide_from_ui": True},
+        )
+        j.on_chat_model_start({}, [[hidden_message]], run_id=uuid4(), tags=["lead_agent"])
+        j.on_chat_model_start(
+            {},
+            [[HumanMessage(content="Real question")]],
+            run_id=uuid4(),
+            tags=["lead_agent"],
+        )
+        await j.flush()
+
+        assert j._first_human_msg == "Real question"
+        assert j.get_completion_data()["message_count"] == 1
+        events = await store.list_events("t1", "r1")
+        human_events = [e for e in events if e["event_type"] == "llm.human.input"]
+        assert len(human_events) == 1
+        assert human_events[0]["content"]["content"] == "Real question"
+
     @pytest.mark.anyio
     async def test_only_first_human_message_captured(self, journal_setup):
         """Subsequent on_chat_model_start calls do not overwrite the first message."""