MCP Configuration for BrainLayer

Use the BrainBar socket bridge for agent MCP wiring. Agents connect to the already-running BrainBar daemon instead of spawning a write-capable Python MCP process. Use the reconnecting stdio bridge rather than raw socat; it keeps the MCP transport alive while the BrainBar socket is replaced and reconnects automatically.

Prerequisites:

• BrainBar is running and owns the configured MCP socket (/tmp/brainbar.sock by default, or BRAINLAYER_MCP_SOCKET).
• The MCP host can resolve brainlayer-mcp-stdio-bridge. Finder-launched macOS apps may not inherit your shell PATH; use an absolute command such as /opt/homebrew/bin/brainlayer-mcp-stdio-bridge when needed.

Add this to Claude, Codex, Cursor, or Gemini MCP settings under mcpServers:

{
  "mcpServers": {
    "brainlayer": {
      "command": "brainlayer-mcp-stdio-bridge"
    }
  }
}

By default the bridge connects to /tmp/brainbar.sock. To point it at a different front socket, set BRAINLAYER_MCP_SOCKET in that MCP entry's env.

The Python brainlayer-mcp entrypoint is still packaged for development and formula installs, but it is not the recommended agent wiring path.

Testing the MCP Server

1. Confirm BrainBar owns the MCP socket:

   test -S /tmp/brainbar.sock
   (printf '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"smoke","version":"0"}}}\n'; sleep 1) \
     | brainlayer-mcp-stdio-bridge \
     | tee /tmp/brainlayer-mcp-smoke.out
   grep '"id":1' /tmp/brainlayer-mcp-smoke.out
   

2. In Claude Code, the tools should appear:

3. brain_search - Unified semantic search (query, file_path, chunk_id, filters)
4. brain_store - Persist memories (ideas, decisions, learnings)
5. brain_recall - Proactive retrieval (context, sessions, summaries)

Old brainlayer_* names still work as backward-compat aliases.