Strudel MCP Server

한국어 | English

An MCP (Model Context Protocol) server that enables LLMs to work with Strudel - a live coding environment for music patterns. This server allows AI assistants to parse, analyze, generate, and transform Strudel patterns.

What is Strudel?

Strudel is a JavaScript port of TidalCycles, a live coding environment for creating music through code. It uses a concise "mini notation" to express complex rhythmic patterns:

s("bd sd [hh hh] cp")  // kick, snare, two hi-hats, clap

What is MCP?

Model Context Protocol (MCP) is an open protocol that enables AI assistants to interact with external tools and services. This server exposes Strudel's pattern engine to any MCP-compatible client.

Features

• Pattern Analysis - Parse mini notation, query pattern events, validate syntax
• Music Theory - Access scales, chords, and voicings
• Code Generation - Generate patterns by style (drums, bass, melody, chords, ambient)
• Pattern Transformation - Apply transformations like fast, slow, rev, jux
• Reference - List available functions, sounds, and samples

Installation

Prerequisites

• Node.js 18 or higher
• npm or pnpm

Setup

# Clone the repository
git clone https://github.com/YOUR_USERNAME/strudel-mcp.git
cd strudel-mcp

# Install dependencies
npm install

# Build the project
npm run build

Usage

With Claude Desktop

Add to your Claude Desktop configuration:

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

{
  "mcpServers": {
    "strudel": {
      "command": "node",
      "args": ["/absolute/path/to/strudel-mcp/dist/index.js"]
    }
  }
}

Then restart Claude Desktop.

With Claude Code

claude mcp add strudel node /absolute/path/to/strudel-mcp/dist/index.js

With MCP Inspector

Test the server interactively:

npm run inspect

Available Tools

Pattern Analysis

Tool	Description	Example Input
strudel_parse_mini	Parse mini notation to AST	{"notation": "bd sd [hh hh] cp"}
strudel_query_pattern	Query events in time range	{"code": "bd sd", "startCycle": 0, "endCycle": 2}
strudel_validate_code	Validate syntax	{"code": "bd sd [hh hh]"}
strudel_explain_pattern	Human-readable explanation	{"notation": "bd(3,8)"}

Music Theory

Tool	Description	Example Input
strudel_list_scales	List available scales	{"filter": "minor"}
strudel_get_scale	Get notes in a scale	{"scale": "pentatonic minor", "root": "A"}
strudel_list_chords	List chord types	{}
strudel_get_voicing	Get chord voicing	{"chord": "Cmaj7"}

Code Generation

Tool	Description	Example Input
strudel_generate_pattern	Generate pattern by style	{"style": "drums", "complexity": "medium"}
strudel_transform_pattern	Apply transformations	{"code": "bd sd", "transformations": ["fast(2)", "rev"]}

Reference

Tool	Description	Example Input
strudel_list_functions	List pattern functions	{"category": "timing"}
strudel_list_sounds	List built-in sounds	{"category": "drums"}

Examples

Parse a Pattern

User: Parse the pattern "bd sd [hh hh] cp"

Tool: strudel_parse_mini
Input: {"notation": "bd sd [hh hh] cp"}

Output:

{
  "notation": "bd sd [hh hh] cp",
  "eventCount": 5,
  "events": [
    {"value": "bd", "whole": "0 -> 0.25"},
    {"value": "sd", "whole": "0.25 -> 0.5"},
    {"value": "hh", "whole": "0.5 -> 0.625"},
    {"value": "hh", "whole": "0.625 -> 0.75"},
    {"value": "cp", "whole": "0.75 -> 1"}
  ]
}

Generate a Drum Pattern

User: Generate a complex drum pattern

Tool: strudel_generate_pattern
Input: {"style": "drums", "complexity": "complex"}

Output:

{
  "style": "drums",
  "complexity": "complex",
  "code": "s(\"bd(3,8), sd(2,8,1), hh*16?0.3, cp(1,4,2)\")",
  "explanation": "Complex polyrhythmic drums using Euclidean patterns"
}

Get Scale Notes

User: What notes are in A minor pentatonic?

Tool: strudel_get_scale
Input: {"scale": "pentatonic minor", "root": "A"}

Output:

{
  "name": "A pentatonic minor",
  "notes": ["A", "C", "D", "E", "G"],
  "usage": "n(\"0 1 2 3 4\").scale(\"A:pentatonic_minor\")"
}

Development

# Build
npm run build

# Run directly
npm start

# Watch mode (rebuild on changes)
npm run dev

# Test with MCP Inspector
npm run inspect

Project Structure

strudel-mcp/
├── src/
│   ├── index.ts        # Main server with all tools
│   └── types.d.ts      # TypeScript declarations for Strudel
├── dist/               # Compiled output
├── package.json
├── tsconfig.json
└── README.md

Dependencies

• @modelcontextprotocol/sdk - MCP SDK
• @strudel/core - Strudel pattern engine
• @strudel/mini - Mini notation parser
• @strudel/tonal - Music theory functions
• tonal - Music theory library
• zod - Schema validation

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see LICENSE for details.

Links

• Strudel - Live coding environment
• Strudel Documentation - Learn Strudel
• TidalCycles - Original Haskell implementation
• MCP Specification - Model Context Protocol

Acknowledgments

• Alex McLean and Felix Roos - Strudel creators
• Anthropic - MCP specification