Polar MCP Server

An MCP (Model Context Protocol) server for the Polar AccessLink API. Connect your Polar fitness data to Claude AI - access workouts, sleep analysis, recovery metrics, heart rate data, and more.

Quick Start (Public Instance)

No setup required! Use our hosted instance:

1. In Claude: Settings → Integrations → Add MCP Server

2. Enter the URL: `https://polar-mcp-server.n-neuhaeusel.workers.dev/mcp`

3. Claude will open an authorization window — log in with your Polar account

4. Start chatting about your fitness data!

Features

25 Tools Available

Supported Devices

• Polar Pacer / Pacer Pro
• Polar Vantage V2 / V3
• Polar Vantage M / M2
• Polar Grit X / Grit X Pro / Grit X2 Pro
• Polar Ignite / Ignite 2 / Ignite 3
• Polar Unite
• And more...

Example Prompts

Once connected, ask Claude:

• "Show me my workouts from last week"
• "How was my sleep last night? Compare it to my weekly average"
• "Analyze my heart rate variability trends"
• "What's my current training load status?"
• "When should I go to bed tonight for optimal recovery?"
• "Export my last run as a GPX file"
• "How many steps did I take this month?"

Self-Hosting

Want to run your own instance? Two deployment options available:

Option 1: Cloudflare Workers (Recommended)

Prerequisites

• Cloudflare account
• Polar AccessLink API credentials

Setup

# Clone and install
git clone https://github.com/NelsonNew/polar-mcp-server.git
cd polar-mcp-server
npm install

# Create KV namespace
npx wrangler kv namespace create OAUTH_KV
# Copy the ID to wrangler.toml

# Set secrets
npx wrangler secret put POLAR_CLIENT_ID
npx wrangler secret put POLAR_CLIENT_SECRET

# Deploy
npm run deploy

After deploying, add the callback URL to your Polar app:

https://YOUR-WORKER.workers.dev/callback

Option 2: Local (Claude Desktop)

# Clone and build
git clone https://github.com/NelsonNew/polar-mcp-server.git
cd polar-mcp-server
npm install && npm run build

# Get access token
export POLAR_CLIENT_ID="your_client_id"
export POLAR_CLIENT_SECRET="your_client_secret"
npm run auth

Add to Claude Desktop config (`~/Library/Application Support/Claude/claude_desktop_config.json`):

{
  "mcpServers": {
    "polar": {
      "command": "node",
      "args": ["/path/to/polar-mcp-server/dist/index.js"],
      "env": {
        "POLAR_ACCESS_TOKEN": "your_access_token"
      }
    }
  }
}

API Reference

All tools use the Polar AccessLink API v3.

Troubleshooting

Privacy

• Your Polar credentials are never stored
• OAuth tokens are managed securely by the Cloudflare Workers OAuth provider
• Each user gets their own isolated MCP session
• No fitness data is logged or stored on our servers

Contributing

Contributions welcome! Please open an issue or PR.

License

MIT

Links

• Polar AccessLink API
• Polar Developer Portal
• MCP Protocol
• Cloudflare Workers