PlayByKey Music Theory

Overview

PlayByKey Music Theory is a Model Context Protocol (MCP) server: Chords, scales, progressions, transposition, and MIDI tools for music theory AI agents. Because it speaks the Model Context Protocol, AI assistants can use PlayByKey Music Theory as a set of callable tools instead of you copy-pasting between apps.

It runs locally: the npm package @playbykey/theory-mcp speaks MCP over stdio on your machine. No credentials are required — it works out of the box. The current release is v1.6.0, published under the MIT license, with source at DigitalBrewLLC/playbykey-dev-tools on GitHub.

On mcp.site, PlayByKey Music Theory sits in the AI & Agents category. Any MCP client can use it — Claude Desktop, Claude Code, Cursor, VS Code, Windsurf, Zed among them — via the install snippets below. If you maintain PlayByKey Music Theory for playbykey.com, claim this listing to verify ownership, earn the Verified badge, and keep the details current.

Installation

// claude_desktop_config.json
{
  "mcpServers": {
    "playbykey_music_theory": {
      "command": "npx",
      "args": [
        "-y",
        "@playbykey/theory-mcp"
      ]
    }
  }
}