Brain MCP Contract

The local endpoint is http://127.0.0.1:8788/mcp. It is loopback-local and token-free for local agents. Port 8787 has a different boundary: health/status is public locally, while protected writes and compatibility routes use the existing bearer policy. WAN bridges are compatibility surfaces, not the local default.

The live server exposes 51 bounded tools. Capability families include governed router recall, semantic recall, GraphRAG, GRIFF-Map evidence, docstore/status, claim verification, receipts, operator intent/outcome/correction continuity, TaskAttempt and artifact IDs. Compatibility recall tool names delegate to the same router/arbiter/grounding implementation; they are not raw bypasses.

The front door is concurrency-safe: synchronous tool implementations run in worker threads. A request exceeding 120 seconds receives a bounded JSON-RPC timeout while the event loop remains available for initialization and other requests.

For architecture or benchmark proof, call retrieval_arbitrate_tool with compact output and inspect candidate_sources, lane diagnostics, dedup, reranker, routing, grounding and map_evidence.