csjoblom/musclesworked-mcp

MCP server for the musclesworked.com exercise-to-muscle mapping API.

Connects Claude Desktop, Claude Code, Cursor, and other MCP clients to 856 exercises and 65 muscles with detailed primary/secondary/stabilizer activation data across 14 muscle groups.

Setup

Get an API key at musclesworked.com/dashboard.

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "musclesworked": {
      "command": "npx",
      "args": ["-y", "musclesworked-mcp"],
      "env": {
        "MUSCLESWORKED_API_KEY": "mw_live_..."
      }
    }
  }
}

Claude Code

claude mcp add musclesworked -- npx -y musclesworked-mcp --api-key mw_live_...

Or add to .mcp.json:

{
  "mcpServers": {
    "musclesworked": {
      "command": "npx",
      "args": ["-y", "musclesworked-mcp", "--api-key", "mw_live_..."]
    }
  }
}

Cursor

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "musclesworked": {
      "command": "npx",
      "args": ["-y", "musclesworked-mcp"],
      "env": {
        "MUSCLESWORKED_API_KEY": "mw_live_..."
      }
    }
  }
}

Tools

Tool	Description
get_muscles_worked	Get primary, secondary, and stabilizer muscles for an exercise
find_exercises	Find exercises targeting a specific muscle with optional filters
analyze_workout	Analyze a workout for coverage, gaps, and imbalances
get_alternatives	Find alternative exercises ranked by muscle overlap
search_exercises	Search exercises by name to discover IDs
search_muscles	Search muscles by name to discover IDs

Example Prompts

• "What muscles does the barbell bench press work?"
• "Find bodyweight exercises for my chest"
• "Analyze my push day: bench press, overhead press, tricep pushdown, lateral raise"
• "What are some alternatives to barbell squats?"
• "Search for exercises that target the hamstrings"

Configuration

Option	Description
--api-key <key>	API key (or set MUSCLESWORKED_API_KEY env var)
MUSCLESWORKED_API_URL	Override base URL (default: https://musclesworked.com)

Development

git clone https://github.com/csjoblom/musclesworked-mcp.git
cd musclesworked-mcp
npm install
npm run build

# Test with MCP Inspector
MUSCLESWORKED_API_KEY=mw_live_... npx @modelcontextprotocol/inspector node dist/index.js

License

MIT