Verification complete. Document and attachment sync handlers are correctly implemented and match the SQLite schema. ## Documents Sync Handlers **Schema (client/schema.py:211-237):** - All NOT NULL fields: id, title, slug, path, tags (default '[]'), created_at, updated_at, version (default 1) - Nullable fields: entity_type, entity_id, deleted_at **Update handler (client/sync.py:674-699):** ✓ All fields properly handled with COALESCE for nullable fields ✓ JSON serialization for tags array field ✓ Version increment logic correct **Insert handler (client/sync.py:860-880):** ✓ All required fields included ✓ Sensible defaults: title='Untitled', slug='', path='', tags=[] ✓ JSON serialization for tags array field ✓ Proper version initialization ## Attachments Sync Handlers **Schema (client/schema.py:244-276):** - NOT NULL fields: id, owner_type, target_id, created_at, updated_at, version (default 1) - All file/URL fields are nullable (filename, path, file, mime_type, size_bytes, url, title, subtitle, icon_url, metadata) **Update handler (client/sync.py:700-737):** ✓ All fields properly handled ✓ owner_type and target_id use COALESCE (correct for updates) ✓ All nullable fields handled with direct assignment ✓ JSON serialization for metadata object ✓ Version increment logic correct **Insert handler (client/sync.py:881-908):** ✓ All required fields included ✓ Defaults: owner_type='issue', target_id='' ✓ All nullable fields properly handled ✓ JSON serialization for metadata object ✓ Proper version initialization ## Edge Cases & Design Notes 1. **Empty string defaults for ID fields**: The handlers use empty strings as defaults for required ID fields (e.g., target_id=''). This pattern is consistent across all entity types (comments, relationships, attachments, documents) and allows inserts to succeed even with incomplete server data, though the data would be semantically invalid. This appears to be a deliberate design choice for robustness. 2. **JSON array fields**: All JSON array fields (tags in documents, metadata in attachments) are properly serialized with json.dumps() on write. 3. **Nullable vs NOT NULL**: The handlers correctly distinguish between nullable fields (using direct assignment or .get() without COALESCE) and NOT NULL fields (using COALESCE in updates to preserve existing values). 4. **Version handling**: Both handlers properly handle version increments (COALESCE(?, version + 1) in updates, defaults to 1 in inserts). ## Test Results All sync tests pass: - test_sync_e2e.py: 11/11 passed - No failures related to documents or attachments ## Recommendation No changes needed. The document and attachment sync handlers are correctly implemented and handle all schema fields, nullable constraints, and edge cases appropriately.