fix(streaming): tighten tool limit terminal guards

api/run_journal.py

@@ -86,7 +86,7 @@ def _terminal_state_for_event(event_name: str, payload) -> str | None:
     if name == "done" or name == "stream_end":
         if isinstance(payload, dict):
             explicit_state = str(payload.get("terminal_state") or "").strip().lower()
-            if explicit_state:
+            if explicit_state in {"tool_limit_reached"}:
                 return explicit_state
         return "completed"
     if name == "cancel":

api/streaming.py

@@ -994,7 +994,7 @@ def _agent_result_tool_limit_reached(result) -> bool:
     if (
         'max_iterations_reached' in haystack
         or 'maximum number of tool-calling iterations' in haystack
-        or 'tool-calling iterations' in haystack and 'maximum' in haystack
+        or ('tool-calling iterations' in haystack and 'maximum' in haystack)
     ):
         return True
     return False
@@ -6796,7 +6796,7 @@ def _run_agent_streaming(
                 # workspace-aware helper from this branch while still
                 # preserving the pre-turn length for downstream self-heal
                 # checks introduced on master.
-                _all_result_messages = _result_messages or []
+                _all_result_messages = result.get('messages') or []
                 _prev_len = len(_previous_context_messages)
                 _assistant_added = _assistant_reply_added_after_current_turn(
                     _all_result_messages,

tests/test_run_journal.py

@@ -110,6 +110,7 @@ def test_terminal_state_classification_distinguishes_crash_from_user_cancel(tmp_
     append_run_event("session_1", "run_failed", "apperror", {"type": "auth_mismatch"}, session_dir=tmp_path)
     append_run_event("session_1", "run_tool_limit", "apperror", {"type": "tool_limit_reached"}, session_dir=tmp_path)
     append_run_event("session_1", "run_tool_limit_done", "done", {"terminal_state": "tool_limit_reached"}, session_dir=tmp_path)
+    append_run_event("session_1", "run_unknown_done", "done", {"terminal_state": "future_unknown_state"}, session_dir=tmp_path)
     append_run_event("session_1", "run_done", "done", {"session": {}}, session_dir=tmp_path)
 
     assert latest_run_summary("session_1", "run_cancelled", session_dir=tmp_path)["terminal_state"] == "interrupted-by-user"
@@ -117,6 +118,7 @@ def test_terminal_state_classification_distinguishes_crash_from_user_cancel(tmp_
     assert latest_run_summary("session_1", "run_failed", session_dir=tmp_path)["terminal_state"] == "errored"
     assert latest_run_summary("session_1", "run_tool_limit", session_dir=tmp_path)["terminal_state"] == "tool_limit_reached"
     assert latest_run_summary("session_1", "run_tool_limit_done", session_dir=tmp_path)["terminal_state"] == "tool_limit_reached"
+    assert latest_run_summary("session_1", "run_unknown_done", session_dir=tmp_path)["terminal_state"] == "completed"
     assert latest_run_summary("session_1", "run_done", session_dir=tmp_path)["terminal_state"] == "completed"
 
 

tests/test_tool_limit_terminal_state.py

@@ -12,7 +12,14 @@ from api.models import Session
 ROOT = Path(__file__).resolve().parents[1]
 
 
-def _run_streaming_with_fake_agent(tmp_path, monkeypatch, agent_result):
+def _run_streaming_with_fake_agent(
+    tmp_path,
+    monkeypatch,
+    agent_result,
+    *,
+    prior_messages=None,
+    prior_context_messages=None,
+):
     session_dir = tmp_path / "sessions"
     session_dir.mkdir()
     monkeypatch.setattr(models, "SESSION_DIR", session_dir)
@@ -38,8 +45,8 @@ def _run_streaming_with_fake_agent(tmp_path, monkeypatch, agent_result):
         title="Tool limit test",
         workspace=str(tmp_path),
         model="gpt-4o",
-        messages=[],
-        context_messages=[],
+        messages=list(prior_messages or []),
+        context_messages=list(prior_context_messages or []),
     )
     session.active_stream_id = stream_id
     session.pending_user_message = "Do the long task."
@@ -124,6 +131,12 @@ def test_synthetic_max_iteration_summary_request_is_dropped_from_agent_result():
     assert "here is the summary" in cleaned[-1]["content"]
 
 
+def test_tool_limit_detection_uses_explicit_boolean_grouping():
+    streaming_py = (ROOT / "api" / "streaming.py").read_text(encoding="utf-8")
+
+    assert "or ('tool-calling iterations' in haystack and 'maximum' in haystack)" in streaming_py
+
+
 def test_historical_synthetic_summary_prompt_does_not_mark_normal_result_as_tool_limit():
     result = {
         "messages": [
@@ -285,3 +298,25 @@ def test_streaming_historical_synthetic_prompt_normal_result_does_not_emit_tool_
     assert "terminal_state" not in done_payloads[-1]
     assert payload["messages"][-1]["role"] == "assistant"
     assert payload["messages"][-1]["content"] == "Current task completed normally."
+
+
+def test_streaming_empty_result_messages_do_not_treat_prior_assistant_as_current_answer(tmp_path, monkeypatch):
+    prior = [
+        {"role": "user", "content": "Earlier task."},
+        {"role": "assistant", "content": "Earlier answer."},
+    ]
+    result = {"messages": []}
+
+    events, payload = _run_streaming_with_fake_agent(
+        tmp_path,
+        monkeypatch,
+        result,
+        prior_messages=prior,
+        prior_context_messages=prior,
+    )
+
+    apperror_payloads = [payload for event, payload in events if event == "apperror"]
+    assert apperror_payloads, "expected silent-failure apperror"
+    assert apperror_payloads[-1]["type"] == "no_response"
+    assert not [payload for event, payload in events if event == "done"]
+    assert payload["messages"][-1]["_error"] is True