Refactor LLMManager's cleanup process to enhance event loop handling during shutdown. Implement best-effort scheduling for cleanup tasks without blocking, and clarify the importance of avoiding new event loop creation to prevent shutdown warnings. Update documentation to guide users on explicit cleanup calls for deterministic behavior.

Author: veithly

spoon_ai/llm/manager.py

@@ -238,17 +238,22 @@ def cleanup_sync():
                 # Try to get the running event loop (Python 3.10+ safe)
                 try:
                     loop = asyncio.get_running_loop()
-                    # If we're inside a running loop, schedule cleanup as a task
+                    # If we're inside a running loop, schedule cleanup as a task (best-effort).
+                    # We intentionally do NOT block here.
                     asyncio.create_task(self.cleanup())
                 except RuntimeError:
-                    # No running loop, create a new one for cleanup
-                    try:
-                        loop = asyncio.new_event_loop()
-                        asyncio.set_event_loop(loop)
-                        loop.run_until_complete(self.cleanup())
-                        loop.close()
-                    except Exception as e:
-                        logger.debug(f"Cleanup skipped: {e}")
+                    # No running loop (common during interpreter shutdown).
+                    #
+                    # IMPORTANT:
+                    # Do not create a new event loop here. Some third-party SDKs
+                    # (notably google-genai) schedule async cleanup tasks in
+                    # `__del__` when a loop is running. Spinning up a loop solely
+                    # for atexit cleanup can therefore cause noisy shutdown warnings:
+                    # "Task was destroyed but it is pending!" / "aclose was never awaited".
+                    #
+                    # Users who need deterministic cleanup should call
+                    # `await get_llm_manager().cleanup()` explicitly.
+                    return
             except Exception as e:
                 # Silently skip cleanup on shutdown errors
                 logger.debug(f"Cleanup error (safe to ignore at shutdown): {e}")