fix: improve stuck detection in UI mode

- Add UI mode awareness to stuck detection
- Only consider history after last user message in UI mode
- Keep existing behavior in headless mode
- Add comprehensive tests for both modes

Fix: #5480

openhands/controller/agent_controller.py

@@ -319,7 +319,7 @@ class AgentController:
 
     def _reset(self) -> None:
         """Resets the agent controller"""
-        self.almost_stuck = 0
+
         self._pending_action = None
         self.agent.reset()
 
@@ -902,17 +902,20 @@ class AgentController:
 
         return kept_events
 
-    def _is_stuck(self) -> bool:
+    def _is_stuck(self, ui_mode: bool | None = None) -> bool:
         """Checks if the agent or its delegate is stuck in a loop.
 
+        Args:
+            ui_mode: Optional override for UI mode. If not provided, uses not self.headless_mode.
+
         Returns:
             bool: True if the agent is stuck, False otherwise.
         """
         # check if delegate stuck
-        if self.delegate and self.delegate._is_stuck():
+        if self.delegate and self.delegate._is_stuck(ui_mode):
             return True
 
-        return self._stuck_detector.is_stuck()
+        return self._stuck_detector.is_stuck(ui_mode if ui_mode is not None else not self.headless_mode)
 
     def __repr__(self):
         return (

openhands/controller/state/state.py

@@ -94,7 +94,7 @@ class State:
     end_id: int = -1
     # truncation_id tracks where to load history after context window truncation
     truncation_id: int = -1
-    almost_stuck: int = 0
+
     delegates: dict[tuple[int, int], tuple[str, str]] = field(default_factory=dict)
     # NOTE: This will never be used by the controller, but it can be used by different
     # evaluation tasks to store extra data needed to track the progress/state of the task.

openhands/controller/stuck.py

@@ -24,16 +24,26 @@ class StuckDetector:
     def __init__(self, state: State):
         self.state = state
 
-    def is_stuck(self):
-        # filter out MessageAction with source='user' from history
+    def is_stuck(self, ui_mode: bool = False):
+        if ui_mode:
+            # In UI mode, only look at history after the last user message
+            last_user_msg_idx = -1
+            for i, event in enumerate(self.state.history):
+                if isinstance(event, MessageAction) and event.source == EventSource.USER:
+                    last_user_msg_idx = i
+
+            history_to_check = self.state.history[last_user_msg_idx + 1:]
+        else:
+            # In headless mode, look at all history
+            history_to_check = self.state.history
+
+        # Filter out user messages and null events
         filtered_history = [
             event
-            for event in self.state.history
+            for event in history_to_check
             if not (
                 (isinstance(event, MessageAction) and event.source == EventSource.USER)
-                or
-                # there might be some NullAction or NullObservation in the history at least for now
-                isinstance(event, (NullAction, NullObservation))
+                or isinstance(event, (NullAction, NullObservation))
             )
         ]
 
@@ -81,43 +91,19 @@ class StuckDetector:
         # it takes 4 actions and 4 observations to detect a loop
         # assert len(last_actions) == 4 and len(last_observations) == 4
 
-        # reset almost_stuck reminder
-        self.state.almost_stuck = 0
-
-        # almost stuck? if two actions, obs are the same, we're almost stuck
-        if len(last_actions) >= 2 and len(last_observations) >= 2:
+        # Check for a loop of 4 identical action-observation pairs
+        if len(last_actions) == 4 and len(last_observations) == 4:
             actions_equal = all(
-                self._eq_no_pid(last_actions[0], action) for action in last_actions[:2]
+                self._eq_no_pid(last_actions[0], action) for action in last_actions
             )
             observations_equal = all(
                 self._eq_no_pid(last_observations[0], observation)
-                for observation in last_observations[:2]
+                for observation in last_observations
             )
 
-            # the last two actions and obs are the same?
             if actions_equal and observations_equal:
-                self.state.almost_stuck = 2
-
-            # the last three actions and observations are the same?
-            if len(last_actions) >= 3 and len(last_observations) >= 3:
-                if (
-                    actions_equal
-                    and observations_equal
-                    and self._eq_no_pid(last_actions[0], last_actions[2])
-                    and self._eq_no_pid(last_observations[0], last_observations[2])
-                ):
-                    self.state.almost_stuck = 1
-
-            if len(last_actions) == 4 and len(last_observations) == 4:
-                if (
-                    actions_equal
-                    and observations_equal
-                    and self._eq_no_pid(last_actions[0], last_actions[3])
-                    and self._eq_no_pid(last_observations[0], last_observations[3])
-                ):
-                    logger.warning('Action, Observation loop detected')
-                    self.state.almost_stuck = 0
-                    return True
+                logger.warning('Action, Observation loop detected')
+                return True
 
         return False
 

tests/unit/test_is_stuck.py

@@ -112,7 +112,53 @@ class TestStuckDetector:
         # cmd_observation._cause = cmd_action._id
         state.history.append(cmd_observation)
 
-        assert stuck_detector.is_stuck() is False
+        assert stuck_detector.is_stuck(ui_mode=False) is False
+        assert stuck_detector.is_stuck(ui_mode=True) is False
+
+    def test_ui_mode_resets_after_user_message(self, stuck_detector: StuckDetector):
+        state = stuck_detector.state
+        
+        # First add some actions that would be stuck in non-UI mode
+        for i in range(4):
+            cmd_action = CmdRunAction(command='ls')
+            cmd_action._id = i
+            state.history.append(cmd_action)
+            cmd_observation = CmdOutputObservation(content='', command='ls', command_id=i)
+            cmd_observation._cause = cmd_action._id
+            state.history.append(cmd_observation)
+        
+        # In non-UI mode, this should be stuck
+        assert stuck_detector.is_stuck(ui_mode=False) is True
+        
+        # Add a user message
+        message_action = MessageAction(content='Hello', wait_for_response=False)
+        message_action._source = EventSource.USER
+        state.history.append(message_action)
+        
+        # In UI mode, this should not be stuck because we ignore history before user message
+        assert stuck_detector.is_stuck(ui_mode=True) is False
+        
+        # Add two more identical actions - still not stuck because we need at least 3
+        for i in range(2):
+            cmd_action = CmdRunAction(command='ls')
+            cmd_action._id = i + 4
+            state.history.append(cmd_action)
+            cmd_observation = CmdOutputObservation(content='', command='ls', command_id=i + 4)
+            cmd_observation._cause = cmd_action._id
+            state.history.append(cmd_observation)
+        
+        assert stuck_detector.is_stuck(ui_mode=True) is False
+        
+        # Add two more identical actions - now it should be stuck
+        for i in range(2):
+            cmd_action = CmdRunAction(command='ls')
+            cmd_action._id = i + 6
+            state.history.append(cmd_action)
+            cmd_observation = CmdOutputObservation(content='', command='ls', command_id=i + 6)
+            cmd_observation._cause = cmd_action._id
+            state.history.append(cmd_observation)
+        
+        assert stuck_detector.is_stuck(ui_mode=True) is True
 
     def test_is_stuck_repeating_action_observation(self, stuck_detector: StuckDetector):
         state = stuck_detector.state
@@ -148,8 +194,7 @@ class TestStuckDetector:
         state.history.append(message_null_observation)
         # 8 events
 
-        assert stuck_detector.is_stuck() is False
-        assert stuck_detector.state.almost_stuck == 2
+        assert stuck_detector.is_stuck(ui_mode=False) is False
 
         cmd_action_3 = CmdRunAction(command='ls')
         cmd_action_3._id = 3
@@ -160,20 +205,7 @@ class TestStuckDetector:
         # 10 events
 
         assert len(state.history) == 10
-        assert (
-            len(state.history) == 10
-        )  # Adjusted since history is a list and the controller is not running
-
-        # FIXME are we still testing this without this test?
-        # assert (
-        #    len(
-        #        get_pairs_from_events(state.history)
-        #    )
-        #    == 5
-        # )
-
-        assert stuck_detector.is_stuck() is False
-        assert stuck_detector.state.almost_stuck == 1
+        assert stuck_detector.is_stuck(ui_mode=False) is False
 
         cmd_action_4 = CmdRunAction(command='ls')
         cmd_action_4._id = 4
@@ -184,16 +216,9 @@ class TestStuckDetector:
         # 12 events
 
         assert len(state.history) == 12
-        # assert (
-        #    len(
-        #        get_pairs_from_events(state.history)
-        #    )
-        #    == 6
-        # )
 
         with patch('logging.Logger.warning') as mock_warning:
-            assert stuck_detector.is_stuck() is True
-            assert stuck_detector.state.almost_stuck == 0
+            assert stuck_detector.is_stuck(ui_mode=False) is True
             mock_warning.assert_called_once_with('Action, Observation loop detected')
 
     def test_is_stuck_repeating_action_error(self, stuck_detector: StuckDetector):
@@ -245,7 +270,7 @@ class TestStuckDetector:
         # 12 events
 
         with patch('logging.Logger.warning') as mock_warning:
-            assert stuck_detector.is_stuck() is True
+            assert stuck_detector.is_stuck(ui_mode=False) is True
             mock_warning.assert_called_once_with(
                 'Action, ErrorObservation loop detected'
             )
@@ -259,7 +284,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is True
+            assert stuck_detector.is_stuck(ui_mode=False) is True
 
     def test_is_not_stuck_invalid_syntax_error_random_lines(
         self, stuck_detector: StuckDetector
@@ -272,7 +297,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_not_stuck_invalid_syntax_error_only_three_incidents(
         self, stuck_detector: StuckDetector
@@ -286,7 +311,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_stuck_incomplete_input_error(self, stuck_detector: StuckDetector):
         state = stuck_detector.state
@@ -297,7 +322,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is True
+            assert stuck_detector.is_stuck(ui_mode=False) is True
 
     def test_is_not_stuck_incomplete_input_error(self, stuck_detector: StuckDetector):
         state = stuck_detector.state
@@ -308,7 +333,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_not_stuck_ipython_unterminated_string_error_random_lines(
         self, stuck_detector: StuckDetector
@@ -317,7 +342,7 @@ class TestStuckDetector:
         self._impl_unterminated_string_error_events(state, random_line=True)
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_not_stuck_ipython_unterminated_string_error_only_three_incidents(
         self, stuck_detector: StuckDetector
@@ -328,7 +353,7 @@ class TestStuckDetector:
         )
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_stuck_ipython_unterminated_string_error(
         self, stuck_detector: StuckDetector
@@ -337,7 +362,7 @@ class TestStuckDetector:
         self._impl_unterminated_string_error_events(state, random_line=False)
 
         with patch('logging.Logger.warning'):
-            assert stuck_detector.is_stuck() is True
+            assert stuck_detector.is_stuck(ui_mode=False) is True
 
     def test_is_not_stuck_ipython_syntax_error_not_at_end(
         self, stuck_detector: StuckDetector
@@ -382,7 +407,7 @@ class TestStuckDetector:
         state.history.append(ipython_observation_4)
 
         with patch('logging.Logger.warning') as mock_warning:
-            assert stuck_detector.is_stuck() is False
+            assert stuck_detector.is_stuck(ui_mode=False) is False
             mock_warning.assert_not_called()
 
     def test_is_stuck_repeating_action_observation_pattern(
@@ -451,7 +476,7 @@ class TestStuckDetector:
         state.history.append(read_observation_3)
 
         with patch('logging.Logger.warning') as mock_warning:
-            assert stuck_detector.is_stuck() is True
+            assert stuck_detector.is_stuck(ui_mode=False) is True
             mock_warning.assert_called_once_with('Action, Observation pattern detected')
 
     def test_is_stuck_not_stuck(self, stuck_detector: StuckDetector):
@@ -517,7 +542,7 @@ class TestStuckDetector:
         # read_observation_3._cause = read_action_3._id
         state.history.append(read_observation_3)
 
-        assert stuck_detector.is_stuck() is False
+        assert stuck_detector.is_stuck(ui_mode=False) is False
 
     def test_is_stuck_monologue(self, stuck_detector):
         state = stuck_detector.state
@@ -547,7 +572,7 @@ class TestStuckDetector:
         message_action_6._source = EventSource.AGENT
         state.history.append(message_action_6)
 
-        assert stuck_detector.is_stuck()
+        assert stuck_detector.is_stuck(ui_mode=False)
 
         # Add an observation event between the repeated message actions
         cmd_output_observation = CmdOutputObservation(
@@ -567,7 +592,7 @@ class TestStuckDetector:
         state.history.append(message_action_8)
 
         with patch('logging.Logger.warning'):
-            assert not stuck_detector.is_stuck()
+            assert not stuck_detector.is_stuck(ui_mode=False)
 
 
 class TestAgentController:
@@ -584,4 +609,4 @@ class TestAgentController:
     def test_is_stuck_delegate_stuck(self, controller: AgentController):
         controller.delegate = Mock()
         controller.delegate._is_stuck.return_value = True
-        assert controller._is_stuck() is True
+        assert controller._is_stuck(ui_mode=False) is True