Music Studio MCP Server

MCP Music Studio

Two-mode creative music studio for AI: scored composition (ABC notation with sheet music) and live performance (Strudel live coding with TidalCycles). Interactive UI renders inline in Claude Desktop, claude.ai, and other MCP clients.

One continuous live set through the widget — every section a hot-swapped re-evaluation on the same clock. Full video: 16:9 1080p60 · 3:4 for phones. Made with dev/perform.html and an OBS Browser Source (see scripts/showcase/).

Quick Start — No Install Required

Paste this URL into any MCP client that supports remote servers:

https://mcp-music-studio.linxule.workers.dev/mcp

Claude Desktop / claude.ai: Settings → Connectors → Add Connector → paste the URL above → done.

Claude Code:

claude mcp add --transport http music-studio https://mcp-music-studio.linxule.workers.dev/mcp

That's it — ask Claude to play a song or create a beat.

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What You Get

Scored Composition (ABC Notation)

Write sheet music → see it rendered → hear it played with multi-instrument audio.

• 8 style presets — rock, jazz, bossa, waltz, march, reggae, folk, classical — one parameter adds drums + bass + chord accompaniment
• All 128 General MIDI instruments — named and fuzzy-matched ("sax" → Soprano Sax); the result text says what it actually resolved to when that isn't what you asked for
• Visual sheet music — notes highlight as they play
• Streaming render — sheet music appears as the AI types
• Edit in place — open the ABC source pane in the widget, fix a bar, re-render without another tool call
• Real transposition — transpose rewrites the notation and the key signature, so the printed score matches what plays
• Swing and count-in — swing is the share of the beat given to its first half (50 = straight, 66 = triplet, 75 = max; ≤50 is no swing), drumIntro adds up to 8 bars of count-in from the style's drum kit
• Selectable sound banks — FluidR3 (default), MusyngKite (fuller), or a lightweight dry bank, switched live from the toolbar
• WAV download — export audio as WAV files directly from the UI
• MIDI download — export a standard MIDI file straight from the score, no playback needed first. It is the score: abcjs applies swing during playback only, so the exported file has none
• get-music-guide — 7 reference topics (instruments, drums, ABC syntax, arrangements, genres, styles, MIDI directives)

Live Performance (Strudel)

Write code → hear it play → edit in a live REPL.

• TidalCycles mini-notation in JavaScript
• 71 drum machine banks + 128 GM instruments + 128 VCSL orchestral/world/percussion samples + built-in synths
• Full effects chain — filters, reverb, delay, FM synthesis
• Editable REPL — users can tweak the code and hear changes instantly
• Live visuals — add .pianoroll() / .punchcard() / .scope() / .spectrum() to animate behind the code (native strudel.cc overlay)
• Hydra shader backgrounds — await initHydra() + Hydra code for fully custom, music-synced WebGL visuals. H(pattern) locks a shader parameter to the sequence, feedStrudel post-processes the piano roll
• Audio-reactive shaders — a.fft[0], a0(), a.setBins(6) and the rest of Hydra's audio API work verbatim, driven by Strudel's own output rather than the microphone (no permission prompt, no room noise)
• visuals preset — one enum value (pianoroll, punchcard, scope, spectrum, hydra-kaleid, hydra-pulse, hydra-wash, hydra-feed) gives a bare pattern something to paint. Never overrides code that already visualises itself
• theme — 39 CodeMirror colour schemes; the visuals stage and its readability scrim are derived from the active theme, so light themes stay readable
• Stage mode — hide the code and let the visuals fill the frame (composes with the host's fullscreen)
• Honest runtime feedback — evaluation errors, unknown sound names, and stops the user triggered are reported back to the model as they happen, so it never answers about a silent widget as if the music were still playing
• Server-side validation — the local server evaluates every Strudel pattern headlessly before answering: the tool result reports layers, events per cycle, tempo, and which sound names are registered (or a syntax error with line:column), so terminal clients get real diagnostics too. (The hosted worker can't — Cloudflare forbids dynamic code generation — and says so.)
• Record & download — capture live audio and export as WAV
• get-strudel-guide — 8 reference topics (mini-notation, sounds, effects, patterns, genres, tips, visuals, advanced)

Shared

• analyze-harmony — chord detection, key detection, progressions, chord scales; answers in both ABC chord symbols and Strudel chord()/note() form
• convert-abc-to-strudel — take a scored melody into the live REPL: bars become mini-notation groups, durations become @ weights, chord symbols become a chord().voicing() line
• search-music-docs — semantic search over strudel.cc and ABCJS documentation
• Click-to-play links — in clients that can't render the inline widget (terminals, CLIs), both play tools return a hosted URL that actually plays. Short pieces travel in the link itself; longer ones are stored for 30 days

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Local Install (Optional)

The remote URL above works without any local setup. If you prefer running locally (offline use, lower latency), install via npm:

CLI One-Liners

# Claude Code
claude mcp add music-studio -- npx -y mcp-music-studio --stdio

# Codex CLI
codex mcp add -- npx -y mcp-music-studio --stdio

# Gemini CLI
gemini mcp add -- npx -y mcp-music-studio --stdio

# OpenCode
opencode mcp add music-studio -- npx -y mcp-music-studio --stdio

JSON Config (Claude Desktop, Cursor, Windsurf, etc.)

{
  "mcpServers": {
    "music-studio": {
      "command": "npx",
      "args": ["-y", "mcp-music-studio", "--stdio"]
    }
  }
}

Add to .vscode/mcp.json — note: uses "servers" not "mcpServers":

{
  "servers": {
    "music-studio": {
      "command": "npx",
      "args": ["-y", "mcp-music-studio", "--stdio"]
    }
  }
}

Add to ~/.cursor/mcp.json:

{
  "mcpServers": {
    "music-studio": {
      "command": "npx",
      "args": ["-y", "mcp-music-studio", "--stdio"]
    }
  }
}

Add to ~/.codeium/windsurf/mcp_config.json:

{
  "mcpServers": {
    "music-studio": {
      "command": "npx",
      "args": ["-y", "mcp-music-studio", "--stdio"]
    }
  }
}

On Windows, npx is a .cmd file and requires a shell wrapper:

{
  "mcpServers": {
    "music-studio": {
      "command": "cmd",
      "args": ["/c", "npx", "-y", "mcp-music-studio", "--stdio"]
    }
  }
}

Clients that support ext-apps render the interactive UI inline automatically (auto mode). For clients that don't (Cherry Studio, CLI environments), use --render-mode:

{
  "mcpServers": {
    "music-studio": {
      "command": "npx",
      "args": ["-y", "mcp-music-studio", "--stdio", "--render-mode", "browser"]
    }
  }
}

Clients without a widget also get a click-to-play link in the tool result, served by the hosted worker — no local render mode needed.

Without --stdio the server listens over Streamable HTTP. That endpoint is unauthenticated, so it binds 127.0.0.1:3001 by default and only accepts browser requests from loopback origins.

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Tools

visuals — none, pianoroll, punchcard, scope, spectrum, hydra-kaleid, hydra-pulse, hydra-wash, hydra-feed. theme — any of the 39 schemes the Strudel REPL ships (strudelTheme, nord, sonicPink, teletext, gruvboxDark, githubLight, …). style — rock, jazz, bossa, waltz, march, reggae, folk, classical.

Prompts

Slash-command / menu entry points, in clients that surface MCP prompts:

0.5.6 — September 14, 2026

Dependency and compatibility maintenance: audited dependency locks, ext-apps v2 widgets, the SDK v1-compatible worker adapter, and validated worker startup. The seven tools, music features and UI controls retain their existing behavior. Builds now synchronize the MCP Registry metadata with the package version, and publishing waits for the npm package to propagate before registry registration.

Development

Use Bun 1.4.2 and Node 24 for development and CI. Dependency updates use the Bun ecosystem so both package manifests and lockfiles stay consistent. The server retains SDK v1 and the worker uses Agents' legacy MCP handler; widgets use ext-apps v2. CI checks both locks for vulnerabilities and exercises the real worker HTTP transport as well as the local/worker parity suite. The worker entry module exports only its fetch handler; test helpers stay in the implementation module because workerd rejects constants as runtime entry points.

bun install
bun run dev      # watch + serve (hot reload)
bun run build    # production build (widgets must be built before the tests)
bun run test     # run tests

dev/ is a local ext-apps host harness for driving the widgets outside a real client — see dev/README.md.

Attribution

Forked from the Sheet Music Server example from MCP ext-apps by Anthropic, licensed under MIT.

Live coding is powered by Strudel — canonical repo at codeberg.org/uzu/strudel (the project moved off GitHub, so the GitHub mirror can be stale). Notation and playback use abcjs; shader backgrounds use hydra-synth.

License

MIT