* refactor: extract compact logic to shared function
Extract the compaction logic from LettaAgentV3.compact() into a
standalone compact_messages() function that can be shared between
the agent and temporal workflows.
Changes:
- Create apps/core/letta/services/summarizer/compact.py with:
- compact_messages(): Core compaction logic
- build_summarizer_llm_config(): LLM config builder for summarization
- CompactResult: Dataclass for compaction results
- Update LettaAgentV3.compact() to use compact_messages()
- Update temporal summarize_conversation_history activity to use
compact_messages() instead of the old Summarizer class
- Add use_summary_role parameter to SummarizeParams
This ensures consistent summarization behavior across different
execution paths and prevents drift as we improve the implementation.
* chore: clean up verbose comments
* fix: correct CompactionSettings import path
* fix: correct count_tokens import from summarizer_sliding_window
* fix: update test patch path for count_tokens_with_tools
After extracting compact logic to compact.py, the test was patching
the old location. Update the patch path to the new module location.
* fix: update test to use build_summarizer_llm_config from compact.py
The function was moved from LettaAgentV3._build_summarizer_llm_config
to compact.py as a standalone function.
* fix: add early check for system prompt size in compact_messages
Check if the system prompt alone exceeds the context window before
attempting summarization. The system prompt cannot be compacted,
so fail fast with SystemPromptTokenExceededError.
* fix: properly propagate SystemPromptTokenExceededError from compact
The exception handler in _step() was not setting the correct stop_reason
for SystemPromptTokenExceededError, which caused the finally block to
return early and swallow the exception.
Add special handling to set stop_reason to context_window_overflow_in_system_prompt
when SystemPromptTokenExceededError is caught.
* revert: remove redundant SystemPromptTokenExceededError handling
The special handling in the outer exception handler is redundant because
stop_reason is already set in the inner handler at line 943. The actual
fix for the test was the early check in compact_messages(), not this
redundant handling.
* fix: correctly re-raise SystemPromptTokenExceededError
The inner exception handler was using 'raise e' which re-raised the outer
ContextWindowExceededError instead of the current SystemPromptTokenExceededError.
Changed to 'raise' to correctly re-raise the current exception. This bug
was pre-existing but masked because _check_for_system_prompt_overflow was
only called as a fallback. The new early check in compact_messages() exposed it.
* revert: remove early check and restore raise e to match main behavior
* fix: set should_continue=False and correctly re-raise exception
- Add should_continue=False in SystemPromptTokenExceededError handler (matching main's _check_for_system_prompt_overflow behavior)
- Fix raise e -> raise to correctly propagate SystemPromptTokenExceededError
Note: test_large_system_prompt_summarization still fails locally but passes on main.
Need to investigate why exception isn't propagating correctly on refactored branch.
* fix: add SystemPromptTokenExceededError handler for post-step compaction
The post-step compaction (line 1066) was missing a SystemPromptTokenExceededError
exception handler. When compact_messages() raised this error, it would be caught
by the outer exception handler which would:
1. Set stop_reason to "error" instead of "context_window_overflow_in_system_prompt"
2. Not set should_continue = False
3. Get swallowed by the finally block (line 1126) which returns early
This caused test_large_system_prompt_summarization to fail because the exception
never propagated to the test.
The fix adds the same exception handler pattern used in the retry compaction flow
(line 941-946), ensuring proper state is set before re-raising.
This issue only affected the refactored code because on main, _check_for_system_prompt_overflow()
was an instance method that set should_continue/stop_reason BEFORE raising. In the refactor,
compact_messages() is a standalone function that cannot set instance state, so the caller
must handle the exception and set the state.
f48b60634f