A missing 'mcp' package made the whole custom_node load fail with ModuleNotFoundError. Now the Agent Emit/Receive nodes register regardless and the bridge prints an actionable install hint (with ComfyUI's python path) instead of crashing. Use __package__ to pick relative vs sys.path import so a broad except no longer masks a missing-dependency error. Adds a no-mcp load test. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>