PlayByKey Music Theory MCP Server

by playbykey Your server? Claim it

local only

PlayByKey Music Theory runs on your own machine — the client starts it, so there is no endpoint to ping. 104 installs a week from npm. Last commit 15 Sep 2026.

Chords, scales, progressions, transposition, and MIDI tools for music theory AI agents.

Installs per day peak 22 · avg 10 · +108% w/w

a month agotoday

104

Installs / week

npm · @playbykey/theory-mcp

Stars

0 open issues

15 Sep 2026

Last commit

3 releases in 90 days

MIT

License

TypeScript

Nothing serious here today

Today is the operative word: we check PlayByKey Music Theory every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add theory-mcp -- npx -y @playbykey/theory-mcp

~/Library/Application Support/Claude/claude_desktop_config.json

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

~/.codex/config.toml

[mcp_servers.theory-mcp]
command = "npx"
args = ["-y", "@playbykey/theory-mcp"]

.cursor/mcp.json

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

.vscode/mcp.json

{
  "servers": {
    "theory-mcp": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@playbykey/theory-mcp"
      ]
    }
  }
}

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PlayByKey Music Theory — questions

Answers built from our own checks of this server.

Why is there no uptime for PlayByKey Music Theory?

PlayByKey Music Theory runs on your own machine over stdio — there is no network address to reach, so uptime cannot be measured for it by anyone. What can be measured is adoption: the npm package @playbykey/theory-mcp was installed 104 times last week.

How do I connect PlayByKey Music Theory?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It runs locally, so the command pulls @playbykey/theory-mcp straight from npm; nothing to host, nothing to sign up for.

How many people use PlayByKey Music Theory?

The npm package @playbykey/theory-mcp was installed 104 times in the last week. Week over week that is +108%. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.

Is PlayByKey Music Theory open source?

Yes — it is published under the MIT licence, written in TypeScript and 1 stars on GitHub. The source link is on this page, so you can read exactly what it does with your data before you connect it.