Quickstart

This gets you from zero to a composed MIDI file in about five minutes.

1. Clone and start the server

bash

git clone https://github.com/deer/music.build
cd music.build
./mvnw exec:java -pl music-server

The server starts on http://localhost:3000/mcp. Leave it running.

The first run downloads Maven dependencies — subsequent starts are instant.

2. Connect Claude Desktop

Add music.build to your Claude Desktop configuration:

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

Windows — %APPDATA%\Claude\claude_desktop_config.json

json

{
  "mcpServers": {
    "music": {
      "url": "http://localhost:3000/mcp"
    }
  }
}

Restart Claude Desktop. The server must be running before Claude connects — start it first, then open Claude.

3. Ask Claude to compose something

In Claude Desktop, try a prompt like:

Compose a 16-bar jazz waltz in F major. Use a lyrical melody in the right hand, a walking bass in the left hand, and light brushed drums. Export to MIDI when done.

Claude will make a series of tool calls — creating voices, setting harmony, loading a drum preset — and finish with export.all. The composed files appear in generated_tracks/ inside your music.build directory.

What to expect

A typical composition session looks like this in the tool call log:

lua

score.set_metadata   → title, tempo, 3/4 time
harmony.set_key      → F major
voice.create         → melody (8 bars)
voice.append         → melody (bars 9–16)
drums.preset         → waltz_jazz pattern
harmony.walking_bass → bass voice from chord progression
score.assign_instrument → melody → Flute, bass → Acoustic Bass
rules.check          → validate meter and voice leading
export.all           → write MIDI + session log

The MIDI file plays back with all voices, instruments, and tempo exactly as the agent specified.

Use a different port

If port 3000 is taken:

bash

PORT=4000 ./mvnw exec:java -pl music-server

Update the url in your Claude Desktop config to match.

Next steps

Installation — full prerequisites and build instructions
Note Syntax — the DSL agents use to write notes
Tools — complete reference for all 47 MCP tools