XERT MCP Server

A Model Context Protocol (MCP) server that connects Claude to the XERT API, providing access to your fitness signature, training load, workouts, and activities.

Features

📊 Fitness Signature - Get your current FTP, LTP, HIE, and Peak Power
🎯 Training Status - Check freshness, training load, and recommended XSS
🏋️ Workout of the Day - AI-powered workout recommendations
📋 Workouts - List, view details, and export (ZWO/ERG)
🚴 Activities - Browse activities with full XSS metrics and MPA data
⬆️ Upload - Upload FIT files for analysis

Installation

Prerequisites

Node.js 18 or later
A XERT account (free or premium)

Setup

Clone the repository:
git clone https://github.com/Milofax/xert-mcp.git cd xert-mcp
Install dependencies:
npm install
Authenticate with XERT:
npm run setup-auth
Enter your XERT email and password when prompted. Tokens will be saved to .env.
Build the project:
npm run build

Configuration

Add to your Claude Desktop config:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{ "mcpServers": { "xert": { "command": "node", "args": ["/path/to/xert-mcp/dist/server.js"] } } }

Replace /path/to/xert-mcp with the actual path to your installation.

Restart Claude Desktop to load the server.

Available Tools

Tool	Description
`xert-get-training-info`	Get fitness signature, training status, load, and WOTD
`xert-list-workouts`	List all your saved workouts
`xert-get-workout`	Get detailed workout intervals
`xert-download-workout`	Export workout as ZWO or ERG file
`xert-list-activities`	List activities in a time range
`xert-get-activity`	Get activity details with XSS metrics
`xert-upload-fit`	Upload a FIT file for analysis

Usage Examples

Ask Claude questions like:

"What's my current FTP and training status?"
"Show me my workout of the day"
"List my activities from the last 7 days"
"What was my XSS breakdown for yesterday's ride?"
"Did I have any breakthroughs this week?"
"Show me my saved workouts"
"Export my 'Sunday Endurance' workout as a ZWO file"

XERT Concepts

FTP - Functional Threshold Power (1-hour sustainable power)
LTP - Lower Threshold Power (fat-burning threshold)
HIE - High Intensity Energy (anaerobic work capacity)
PP - Peak Power (maximum instantaneous power)
XSS - Xert Strain Score (training load metric)
MPA - Maximum Power Available (real-time power limit)

Development

# Run in development mode npm run dev # Build for production npm run build # Start production server npm start

Token Management

The server handles tokens automatically:

Access tokens expire after 7 days
Refresh tokens expire after 6 months
Tokens are stored in xert-tokens.json (created automatically)
On 401 errors, tokens are refreshed automatically
New tokens are persisted to survive server restarts

If authentication fails completely, run npm run setup-auth again.

MCP Funnel / Environment Variables

When using mcp-funnel or similar tools, tokens from xert-tokens.json take priority over environment variables. This ensures refreshed tokens are used even when env vars contain outdated values.