The sync thread is a daemon thread killed without cleanup on SIGTERM. Mid-write kills could corrupt the index. Recoverable (full reindex) but slow. See [[Tasks/Semantic_Search_Architecture]].
+
### ~~FAISS index corruption risk~~ ✅ RESOLVED (2026-03-15)
+
Sync thread removed. Index updates now happen through page lifecycle hooks only. No more daemon thread killed without cleanup.
### OAuth token refresh
Claude.ai token refresh hasn't been tested. If tokens expire after 1 hour and refresh fails, users lose their MCP connection.