coros-workout-mcp

MCP server for creating COROS strength workouts via the Training Hub API. Lets Claude design workouts and push them directly to your COROS watch.

See the MCP in action: YouTube walkthrough

Disclaimer

This is an unofficial, community-driven project. It is not affiliated with, endorsed by, or connected to COROS in any way.

This server communicates with the COROS Training Hub using a reverse-engineered, undocumented API that may change or break without notice. Use it at your own risk.

COROS is a trademark of COROS Wearables, Inc. This project is provided as-is with no warranty — see LICENSE for details.

Setup

cd coros-workout-mcp
npm install
npm run build

Usage with Claude Code

claude mcp add coros-workout -- node /path/to/coros-workout-mcp/dist/src/index.js

To use env var auth (avoids typing credentials in conversation):

claude mcp add coros-workout -e COROS_EMAIL=you@example.com -e COROS_PASSWORD=yourpass -e COROS_REGION=eu -- node /path/to/coros-workout-mcp/dist/src/index.js

Usage with Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "coros-workout": {
      "command": "/path/to/node",
      "args": ["/path/to/coros-workout-mcp/dist/src/index.js"],
      "env": {
        "COROS_EMAIL": "you@example.com",
        "COROS_PASSWORD": "yourpass",
        "COROS_REGION": "eu"
      }
    }
  }
}

Node.js 18+ required — this server uses native fetch() which was added in Node 18.

Troubleshooting fetch is not defined: Claude Desktop is a GUI app that doesn't inherit your shell PATH, so node binaries installed via version managers (mise, nvm, fnm, volta) won't be found. Use the full absolute path to your node binary in "command":

which node        # e.g. /Users/you/.mise/shims/node
node --version    # confirm it's 18+

Common locations:

• mise: ~/.local/share/mise/installs/node/<version>/bin/node
• nvm: ~/.nvm/versions/node/<version>/bin/node
• fnm: ~/.local/share/fnm/node-versions/<version>/installation/bin/node
• Homebrew: /opt/homebrew/bin/node

Tools

Tool	Description
authenticate_coros	Log in with email/password (or auto-login from env vars)
check_coros_auth	Verify current auth status
search_exercises	Search ~383 exercises by name, muscle, body part, equipment
create_workout	Build and push a strength workout to COROS
update_exercises	Fetch the latest exercise catalog from COROS and rebuild locally
list_workouts	List existing workouts

Example conversation

"Search for chest exercises with bodyweight"

"Create a workout called 'Quick Push' with 4x15 Push-ups, 3x10 Diamond Push-ups, and 3x20 Decline Push-ups with 45s rest"

Updating the exercise catalog

The bundled exercise catalog (data/exercises.json) is a static snapshot. If COROS adds new exercises, use the update_exercises tool to refresh it. This fetches the latest exercises from the COROS API and i18n strings from the CDN, rebuilds the catalog, and reloads the in-memory cache — all in a single tool call. Requires authentication.

Auth notes

• Region: eu (Europe) or us (US). Defaults to eu.
• Session conflict: Logging in via this API invalidates your COROS web app session, and vice versa.
• Auth tokens are stored at ~/.config/coros-workout-mcp/auth.json (mode 0600).

Development

npm test           # Run unit tests
npm run test:watch # Watch mode
npm run build      # Compile TypeScript