Add compaction settings to ADE (#9667)

* add compaction settings to ADE, add get default prompt for updated mode route

* update patch to auto set prompt on mode change, related ade changes

* reset api and update test

* feat: add compaction configuration translation keys for fr and cn

Add ADE/CompactionConfiguration translation keys to fr.json and cn.json
to match the new keys added in en.json.

Co-authored-by: Christina Tong <christinatong01@users.noreply.github.com>

🤖 Generated with [Letta Code](https://letta.com)

Co-Authored-By: Letta <noreply@letta.com>

* type/translation/etc fixes

* fix typing

* update model selector path w/ change from main

* import mode from sdk

---------

Co-authored-by: letta-code <248085862+letta-code@users.noreply.github.com>
Co-authored-by: Letta <noreply@letta.com>

letta/services/agent_manager.py

@@ -24,8 +24,7 @@ from letta.constants import (
     INCLUDE_MODEL_KEYWORDS_BASE_TOOL_RULES,
     RETRIEVAL_QUERY_DEFAULT_PAGE_SIZE,
 )
-
-from letta.errors import LettaAgentNotFoundError, LettaError, LettaInvalidArgumentError
+from letta.errors import LettaError
 from letta.helpers import ToolRulesSolver
 from letta.helpers.datetime_helpers import get_utc_time
 from letta.log import get_logger
@@ -789,6 +788,21 @@ class AgentManager:
                     agent.agent_type,
                 )
 
+            # Upsert compaction_settings: merge incoming partial update with existing settings
+            if agent_update.compaction_settings is not None:
+                # If mode changed, update the prompt to the default for the new mode
+                if agent.compaction_settings is not None and agent_update.compaction_settings.mode != agent.compaction_settings.mode:
+                    from letta.services.summarizer.summarizer_config import get_default_prompt_for_mode
+
+                    agent_update.compaction_settings.prompt = get_default_prompt_for_mode(agent_update.compaction_settings.mode)
+
+                # Fill in unchanged fields from existing settings
+                if agent.compaction_settings is not None:
+                    changed_fields = agent_update.compaction_settings.model_fields_set
+                    for field in agent.compaction_settings.model_fields:
+                        if field not in changed_fields:
+                            setattr(agent_update.compaction_settings, field, getattr(agent.compaction_settings, field))
+
             scalar_updates = {
                 "name": agent_update.name,
                 "system": agent_update.system,

letta/services/summarizer/summarizer_config.py

@@ -11,7 +11,7 @@ from letta.settings import summarizer_settings
 def get_default_summarizer_model(provider_type: ProviderType) -> str | None:
     """Get default model for summarization for given provider type."""
     summarizer_defaults = {
-        ProviderType.anthropic: "anthropic/claude-haiku-4-5-20251001",
+        ProviderType.anthropic: "anthropic/claude-haiku-4-5",
         ProviderType.openai: "openai/gpt-5-mini",
         ProviderType.google_ai: "google_ai/gemini-2.5-flash",
     }

tests/managers/test_agent_manager.py

@@ -366,6 +366,8 @@ async def test_compaction_settings_model_uses_separate_llm_config_for_summarizat
 async def test_create_agent_sets_default_compaction_model_anthropic(server: SyncServer, default_user):
     """When no compaction_settings provided for Anthropic agent, default haiku model should be set."""
     from letta.schemas.agent import CreateAgent
+    from letta.schemas.enums import ProviderType
+    from letta.services.summarizer.summarizer_config import get_default_summarizer_model
 
     await server.init_async(init_with_default_org_and_user=True)
 
@@ -384,7 +386,7 @@ async def test_create_agent_sets_default_compaction_model_anthropic(server: Sync
 
     # Should have default haiku model set
     assert agent.compaction_settings is not None
-    assert agent.compaction_settings.model == "anthropic/claude-haiku-4-5-20251001"
+    assert agent.compaction_settings.model == get_default_summarizer_model(ProviderType.anthropic)
 
 
 @pytest.mark.asyncio
@@ -808,6 +810,79 @@ async def test_update_agent_compaction_settings(server: SyncServer, comprehensiv
     assert updated_agent.compaction_settings.prompt_acknowledgement == False
 
 
+@pytest.mark.asyncio
+async def test_update_agent_partial_compaction_settings(server: SyncServer, comprehensive_test_agent_fixture, default_user):
+    """Test that an agent's compaction_settings can be upserted."""
+    from letta.services.summarizer.summarizer_config import get_default_prompt_for_mode
+
+    agent, _ = comprehensive_test_agent_fixture
+
+    # Create new compaction settings
+    original_compaction_settings = agent.compaction_settings.model_copy()
+
+    new_compaction_settings = CompactionSettings(
+        mode="all",
+        prompt_acknowledgement=True,
+        clip_chars=3000,
+    )
+
+    # Update agent with compaction settings
+    update_agent_request = UpdateAgent(
+        compaction_settings=new_compaction_settings,
+    )
+
+    updated_agent = await server.agent_manager.update_agent_async(agent.id, update_agent_request, actor=default_user)
+
+    # Verify compaction settings were updated correctly
+    assert updated_agent.compaction_settings is not None
+    assert updated_agent.compaction_settings.model == original_compaction_settings.model
+    assert updated_agent.compaction_settings.model_settings == original_compaction_settings.model_settings
+    assert updated_agent.compaction_settings.sliding_window_percentage == original_compaction_settings.sliding_window_percentage
+    assert updated_agent.compaction_settings.mode == "all"
+    assert updated_agent.compaction_settings.clip_chars == 3000
+    assert updated_agent.compaction_settings.prompt == get_default_prompt_for_mode("all")
+    assert updated_agent.compaction_settings.prompt_acknowledgement == True
+
+
+@pytest.mark.asyncio
+async def test_update_agent_partial_compaction_settings_same_mode(server: SyncServer, comprehensive_test_agent_fixture, default_user):
+    """Test that if the mode stays the same without a prompt passed in, the prompt is not updated."""
+
+    agent, _ = comprehensive_test_agent_fixture
+
+    update_agent_request = UpdateAgent(
+        compaction_settings=CompactionSettings(mode="sliding_window", prompt="This is a fake prompt."),
+    )
+    updated_agent = await server.agent_manager.update_agent_async(agent.id, update_agent_request, actor=default_user)
+
+    assert updated_agent.compaction_settings is not None
+    assert updated_agent.compaction_settings.prompt == "This is a fake prompt."
+
+    # Create new compaction settings
+    original_compaction_settings = updated_agent.compaction_settings.model_copy()
+
+    new_compaction_settings = CompactionSettings(
+        mode="sliding_window",
+        model="openai/gpt-4o-mini",
+    )
+
+    # Update agent with compaction settings
+    update_agent_request = UpdateAgent(
+        compaction_settings=new_compaction_settings,
+    )
+
+    final_agent = await server.agent_manager.update_agent_async(updated_agent.id, update_agent_request, actor=default_user)
+
+    # Verify compaction settings were updated correctly
+    assert final_agent.compaction_settings is not None
+    assert final_agent.compaction_settings.sliding_window_percentage == original_compaction_settings.sliding_window_percentage
+    assert final_agent.compaction_settings.prompt == original_compaction_settings.prompt
+    assert final_agent.compaction_settings.clip_chars == original_compaction_settings.clip_chars
+    assert final_agent.compaction_settings.prompt_acknowledgement == original_compaction_settings.prompt_acknowledgement
+    assert final_agent.compaction_settings.mode == "sliding_window"
+    assert final_agent.compaction_settings.model == "openai/gpt-4o-mini"
+
+
 @pytest.mark.asyncio
 async def test_agent_file_defaults_based_on_context_window(server: SyncServer, default_user, default_block):
     """Test that file-related defaults are set based on the model's context window size"""