marta-mcp

An MCP server for Atlanta MARTA real-time transit data. Ask Claude things like "When's the next northbound Red Line train at Midtown?" or "Where are the buses on route 110 right now?"

Tools

Related MCP server: mcp-stm-montevideo

API key setup

Rail data requires a free MARTA API key — register here.

The key is never stored in this project or in your MCP client config. The server reads it from, in order:

1. The MARTA_API_KEY environment variable

2. ~/.marta/config.json:

   { "api_key": "your-key-here" }

The easiest way to create the config file:

uvx --from git+https://github.com/LordPsycho202/marta-mcp marta-mcp-config <your-key>

Installation

Option 1 — Claude Desktop extension (one-click)

Requires uv to be installed.

Download marta-mcp.dxt (or .mcpb — same file, newer name) from the latest release and double-click it, or drag it into Claude Desktop's Settings → Extensions. No JSON editing needed.

The extension is a thin manifest: Claude Desktop launches the server with uvx --from git+<this repo>, fetching the package and its dependencies on first run — so it works on any OS and always tracks the repo's main branch.

Build it yourself (requires Node.js):

bash scripts/build_dxt.sh          # macOS / Linux
powershell -ExecutionPolicy Bypass -File scripts\build_dxt.ps1   # Windows

Option 2 — uvx straight from GitHub

Add to your MCP client config (e.g. claude_desktop_config.json):

{
  "mcpServers": {
    "marta": {
      "command": "uvx",
      "args": ["--from", "git+https://github.com/LordPsycho202/marta-mcp", "marta-mcp"]
    }
  }
}

Option 3 — local clone

git clone https://github.com/LordPsycho202/marta-mcp
cd marta-mcp
uv run marta-mcp

Development

uv sync
uv run pytest          # live smoke tests against MARTA's APIs

Notes

• Bus route_id values are MARTA's internal GTFS identifiers, which don't always match the public route numbers. Pair this server with MARTA's static GTFS feed if you need the mapping.

• This project is not affiliated with or endorsed by MARTA. MARTA's marks may not be used without written authorization.

License

MIT