Marrow MCP server

marrow-mcp

Give your AI agents read-only access to your own Apple Health data.

Marrow is a free iOS app that tracks 178 health data series - 172 Apple Health types plus its own meal diary and set-by-set weightlifting log. This repo is its self-hosted companion server: one Python file, standard library only, that keeps a SQLite mirror of your data on hardware you own and serves it over the Model Context Protocol so agents can query it 24/7, phone in your pocket.

Nothing here talks to a cloud. Data flows phone → your machine, full stop.

Run it

python3 marrow_server.py                      # prints a pairing URL
python3 marrow_server.py --port 8800 --data ./data

or

docker compose up -d

Open the pairing URL on any screen, then in Marrow: Server → Pair with a server → scan. From then on the app's background pushes keep the mirror current with the app closed.

Connect an agent

The server speaks MCP over Streamable HTTP (JSON-RPC 2.0, protocol version 2025-06-18), authenticated with a bearer token it generates on first run and prints alongside the pairing link.

Claude Code

claude mcp add --transport http marrow \
  http://<server-ip>:8800/mcp \
  --header "Authorization: Bearer <mcp token>"

Claude Desktop, one click

Download marrow.mcpb, double-click it, and Claude Desktop installs the extension and asks for the URL and token. No terminal involved. (The bundle is a tiny zero-dependency bridge in mcpb/; it forwards Claude's stdio to your Marrow URL and nothing else.)

Claude Desktop (manual), Cursor, or anything using an mcp.json

{
  "mcpServers": {
    "marrow": {
      "type": "http",
      "url": "http://<server-ip>:8800/mcp",
      "headers": { "Authorization": "Bearer <mcp token>" }
    }
  }
}

Check it by hand

curl -s http://<server-ip>:8800/mcp \
  -H "Authorization: Bearer <mcp token>" \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'

Tools

All read-only. Nothing an agent can call writes to your health record.

Then ask your agent things like "how did my sleep change once I started training in the mornings?" and let it go and look.

Why not the built-in Claude or ChatGPT connector?

Both Claude (Pro/Max, US) and ChatGPT now read Apple Health natively. Use them if that is all you need. They stop where this server starts:

Shortened. The full README is on GitHub.