Set default condenser to ConversationWindowCondenser (#10031)

Co-authored-by: Calvin Smith <calvin@all-hands.dev>
Co-authored-by: openhands <openhands@all-hands.dev>

openhands/cli/settings.py

@@ -23,7 +23,10 @@ from openhands.cli.utils import (
 )
 from openhands.controller.agent import Agent
 from openhands.core.config import OpenHandsConfig
-from openhands.core.config.condenser_config import NoOpCondenserConfig
+from openhands.core.config.condenser_config import (
+    CondenserPipelineConfig,
+    ConversationWindowCondenserConfig,
+)
 from openhands.core.config.utils import OH_DEFAULT_AGENT
 from openhands.memory.condenser.impl.llm_summarizing_condenser import (
     LLMSummarizingCondenserConfig,
@@ -472,12 +475,21 @@ async def modify_llm_settings_advanced(
 
     agent_config = config.get_agent_config(config.default_agent)
     if enable_memory_condensation:
-        agent_config.condenser = LLMSummarizingCondenserConfig(
-            llm_config=llm_config,
-            type='llm',
+        agent_config.condenser = CondenserPipelineConfig(
+            type='pipeline',
+            condensers=[
+                ConversationWindowCondenserConfig(type='conversation_window'),
+                # Use LLMSummarizingCondenserConfig with the custom llm_config
+                LLMSummarizingCondenserConfig(
+                    llm_config=llm_config, type='llm', keep_first=4, max_size=120
+                ),
+            ],
         )
+
     else:
-        agent_config.condenser = NoOpCondenserConfig(type='noop')
+        agent_config.condenser = ConversationWindowCondenserConfig(
+            type='conversation_window'
+        )
     config.set_agent_config(agent_config)
 
     settings = await settings_store.load()

openhands/core/config/agent_config.py

@@ -2,7 +2,10 @@ from __future__ import annotations
 
 from pydantic import BaseModel, ConfigDict, Field, ValidationError
 
-from openhands.core.config.condenser_config import CondenserConfig, NoOpCondenserConfig
+from openhands.core.config.condenser_config import (
+    CondenserConfig,
+    ConversationWindowCondenserConfig,
+)
 from openhands.core.config.extended_config import ExtendedConfig
 from openhands.core.logger import openhands_logger as logger
 from openhands.utils.import_utils import get_impl
@@ -44,7 +47,11 @@ class AgentConfig(BaseModel):
     enable_som_visual_browsing: bool = Field(default=True)
     """Whether to enable SoM (Set of Marks) visual browsing."""
     condenser: CondenserConfig = Field(
-        default_factory=lambda: NoOpCondenserConfig(type='noop')
+        # The default condenser is set to the conversation window condenser -- if
+        # we use NoOp and the conversation hits the LLM context length limit,
+        # the agent will generate a condensation request which will never be
+        # handled.
+        default_factory=lambda: ConversationWindowCondenserConfig()
     )
     extended: ExtendedConfig = Field(default_factory=lambda: ExtendedConfig({}))
     """Extended configuration for the agent."""

tests/unit/test_agents.py

@@ -249,6 +249,7 @@ def test_step_with_no_pending_actions(mock_state: State):
     llm.completion = Mock(return_value=mock_response)
     llm.is_function_calling_active = Mock(return_value=True)  # Enable function calling
     llm.is_caching_prompt_active = Mock(return_value=False)
+    llm.format_messages_for_llm = Mock(return_value=[])  # Mock message formatting
 
     # Create agent with mocked LLM
     config = AgentConfig()
@@ -269,6 +270,10 @@ def test_step_with_no_pending_actions(mock_state: State):
     initial_user_message._source = EventSource.USER
     mock_state.history = [initial_user_message]
 
+    # Mock the view returned by condenser
+    mock_view = View(events=mock_state.history)
+    mock_state.view = mock_view
+
     action = agent.step(mock_state)
     assert isinstance(action, MessageAction)
     assert action.content == 'Task completed'

tests/unit/test_cli_settings.py

@@ -19,16 +19,24 @@ from openhands.storage.settings.file_settings_store import FileSettingsStore
 
 # Mock classes for condensers
 class MockLLMSummarizingCondenserConfig:
-    def __init__(self, llm_config, type):
+    def __init__(self, llm_config, type, keep_first=4, max_size=120):
         self.llm_config = llm_config
         self.type = type
+        self.keep_first = keep_first
+        self.max_size = max_size
 
 
-class MockNoOpCondenserConfig:
+class MockConversationWindowCondenserConfig:
     def __init__(self, type):
         self.type = type
 
 
+class MockCondenserPipelineConfig:
+    def __init__(self, type, condensers):
+        self.type = type
+        self.condensers = condensers
+
+
 class TestDisplaySettings:
     @pytest.fixture
     def app_config(self):
@@ -467,7 +475,13 @@ class TestModifyLLMSettingsAdvanced:
         'openhands.cli.settings.LLMSummarizingCondenserConfig',
         MockLLMSummarizingCondenserConfig,
     )
-    @patch('openhands.cli.settings.NoOpCondenserConfig', MockNoOpCondenserConfig)
+    @patch(
+        'openhands.cli.settings.ConversationWindowCondenserConfig',
+        MockConversationWindowCondenserConfig,
+    )
+    @patch(
+        'openhands.cli.settings.CondenserPipelineConfig', MockCondenserPipelineConfig
+    )
     async def test_modify_llm_settings_advanced_success(
         self, mock_confirm, mock_session, mock_list_agents, app_config, settings_store
     ):
@@ -521,7 +535,10 @@ class TestModifyLLMSettingsAdvanced:
         'openhands.cli.settings.LLMSummarizingCondenserConfig',
         MockLLMSummarizingCondenserConfig,
     )
-    @patch('openhands.cli.settings.NoOpCondenserConfig', MockNoOpCondenserConfig)
+    @patch(
+        'openhands.cli.settings.ConversationWindowCondenserConfig',
+        MockConversationWindowCondenserConfig,
+    )
     async def test_modify_llm_settings_advanced_user_cancels(
         self, mock_confirm, mock_session, mock_list_agents, app_config, settings_store
     ):
@@ -548,7 +565,10 @@ class TestModifyLLMSettingsAdvanced:
         'openhands.cli.settings.LLMSummarizingCondenserConfig',
         MockLLMSummarizingCondenserConfig,
     )
-    @patch('openhands.cli.settings.NoOpCondenserConfig', MockNoOpCondenserConfig)
+    @patch(
+        'openhands.cli.settings.ConversationWindowCondenserConfig',
+        MockConversationWindowCondenserConfig,
+    )
     async def test_modify_llm_settings_advanced_invalid_agent(
         self,
         mock_print,
@@ -599,7 +619,10 @@ class TestModifyLLMSettingsAdvanced:
         'openhands.cli.settings.LLMSummarizingCondenserConfig',
         MockLLMSummarizingCondenserConfig,
     )
-    @patch('openhands.cli.settings.NoOpCondenserConfig', MockNoOpCondenserConfig)
+    @patch(
+        'openhands.cli.settings.ConversationWindowCondenserConfig',
+        MockConversationWindowCondenserConfig,
+    )
     async def test_modify_llm_settings_advanced_user_rejects_save(
         self, mock_confirm, mock_session, mock_list_agents, app_config, settings_store
     ):

tests/unit/test_config.py

@@ -16,6 +16,7 @@ from openhands.core.config import (
     load_openhands_config,
 )
 from openhands.core.config.condenser_config import (
+    ConversationWindowCondenserConfig,
     LLMSummarizingCondenserConfig,
     NoOpCondenserConfig,
     RecentEventsCondenserConfig,
@@ -680,7 +681,7 @@ def test_agent_config_condenser_with_no_enabled():
     """Test default agent condenser with enable_default_condenser=False."""
     config = OpenHandsConfig(enable_default_condenser=False)
     agent_config = config.get_agent_config()
-    assert isinstance(agent_config.condenser, NoOpCondenserConfig)
+    assert isinstance(agent_config.condenser, ConversationWindowCondenserConfig)
 
 
 def test_sandbox_volumes_toml(default_config, temp_toml_file):
@@ -907,9 +908,9 @@ def test_default_condenser_behavior_disabled(default_config, temp_toml_file):
     default_config.enable_default_condenser = False
     load_from_toml(default_config, temp_toml_file)
 
-    # Verify the agent config uses NoOpCondenserConfig
+    # Verify the agent config uses ConversationWindowCondenserConfig
     agent_config = default_config.get_agent_config()
-    assert isinstance(agent_config.condenser, NoOpCondenserConfig)
+    assert isinstance(agent_config.condenser, ConversationWindowCondenserConfig)
 
 
 def test_default_condenser_explicit_toml_override(default_config, temp_toml_file):