Skip to main content
Glama
tubone24

MIDI MCP Server

by tubone24
OverviewSchemaRelated ServersScoreDiscussions
TypeScript
Hybrid

MIDI MCP Server

A Model Context Protocol (MCP) server for AI-driven MIDI composition. Generate MIDI files from structured JSON data, with chord name support, an interactive piano-roll preview UI, and multiple deployment modes.

demo

Looking for the Agent Skills approach? It composes better songs with less context: tubone24/midi-agent-skill

Features

  • Two MCP tools: create_midi (with interactive preview UI) and parse_chord

  • Rich pitch input: MIDI numbers, note name strings ("C4"), pitch arrays, or chord names ("Cmaj7")

  • Chord library: 25+ chord qualities — major, minor, dim, aug, 7th, maj7, m7, sus2, sus4, power, and more

  • Flexible durations: numeric beats, standard strings ('4', '8'), dotted ('d4'), triplet ('T8')

  • Music theory resources: 7 built-in reference documents accessible as MCP resources

  • Three transport modes: stdio, HTTP, or Cloudflare Workers (remote)

  • MCP App UI: Piano-roll visualization and audio playback rendered directly in the conversation

Deployment Options

Option A — Remote (Cloudflare Workers)

A pre-deployed remote server is available:

https://midi-mcp-server.tubone24.workers.dev/mcp

Add it to any MCP client that supports Streamable HTTP (e.g., Claude.ai):

{
  "mcpServers": {
    "midi": {
      "type": "http",
      "url": "https://midi-mcp-server.tubone24.workers.dev/mcp"
    }
  }
}

Option B — Local stdio (recommended for desktop clients)

Build and configure as a local stdio server:

npm install
npm run build
{
  "mcpServers": {
    "musicComposer": {
      "command": "node",
      "args": ["/path/to/midi-mcp-server/build/index.js"]
    }
  }
}

Option C — Local HTTP

Run as a local Streamable HTTP server:

node build/index.js --http
# or with a custom port:
node build/index.js --http --port=8080

The server exposes:

  • POST /mcp — MCP Streamable HTTP endpoint

  • GET /health — Health check ({"status":"ok","version":"0.2.0"})

Tools

create_midi

Generate a MIDI file from structured composition data. Returns base64-encoded MIDI and renders an interactive piano-roll preview with audio playback in supported MCP clients (MCP App).

mid

Input

Field

Type

Required

Description

title

string

✓

Title of the composition

composition

object

✓

Composition data (see schema below)

Output (structured content)

Field

Type

Description

midiBase64

string

Base64-encoded MIDI file data

title

string

Composition title

bpm

number

Tempo used

trackCount

number

Number of tracks generated

parse_chord

Parse a chord name and return its component MIDI pitches and note names. Useful for understanding voicings before composing.

Input

Field

Type

Required

Description

chord

string

✓

Chord name, e.g. "Cmaj7", "F#m7", "G7sus4"

octave

number

—

Root octave (default: 4)

Output example

{
  "chord": "Cmaj7",
  "octave": 4,
  "midiNumbers": [60, 64, 67, 71],
  "noteNames": ["C4", "E4", "G4", "B4"]
}

Composition Schema

{
  "bpm": 120,                              // tempo (also accepted: "tempo")
  "timeSignature": { "numerator": 4, "denominator": 4 },  // optional, default 4/4
  "tracks": [
    {
      "name": "Piano",                     // optional
      "instrument": 0,                     // GM program number 0–127 (optional)
      "notes": [
        {
          "pitch": 60,                     // MIDI number, note name "C4", or array [60, 64, 67]
          "chord": "Cmaj7",                // OR use chord name (overrides pitch)
          "beat": 1,                       // beat position (1-based); OR use startTime
          "startTime": 0,                  // tick offset (alias: "time")
          "duration": "4",                 // see Duration Reference below
          "velocity": 100,                 // 0–127 (optional, default 100)
          "channel": 0                     // MIDI channel 0–15 (optional)
        }
      ]
    }
  ]
}

Pitch Input Formats

Format

Example

Description

MIDI number

60

Standard MIDI note number (0–127)

Note name

"C4"

Letter + optional accidental + octave

Pitch array

[60, 64, 67]

Multiple pitches played simultaneously

Chord field

chord: "Cmaj7"

Chord name expanded automatically

Supported accidentals: # (sharp), b (flat). Examples: "F#5", "Bb3".

Duration Reference

Value

Description

'1'

Whole note

'2'

Half note

'4'

Quarter note

'8'

Eighth note

'16'

Sixteenth note

'32'

Thirty-second note

'd1' 'd2' 'd4' 'd8' 'd16'

Dotted variants

'dd4'

Double-dotted quarter

'T4' 'T8' …

Triplet variants

4 (number)

Beat-based: 1=quarter, 2=half, 4=whole, 0.5=eighth

Supported Chord Qualities

Quality

Example

Description

(none) / maj

C, Cmaj

Major

m / min

Dm

Minor

dim

Bdim

Diminished

aug

Eaug

Augmented

7

G7

Dominant 7th

maj7 / M7

Cmaj7

Major 7th

m7 / min7

Am7

Minor 7th

dim7

Bdim7

Diminished 7th

m7b5

Bm7b5

Half-diminished

aug7

Eaug7

Augmented 7th

6 / m6

C6, Am6

6th

9 / maj9 / m9

G9

9th variants

add9

Cadd9

Add 9th

11 / 13

C11

Extended

sus2 / sus4

Gsus4

Suspended

7sus4 / 7sus2

G7sus4

7th suspended

power / 5

G5

Power chord

MCP Resources

The server exposes 7 music theory reference documents as MCP resources:

URI

Description

music-theory://harmony

Intervals, chord types, diatonic chords, cadences, voice leading

music-theory://chord-progressions

Common progressions by mood/genre, substitutions, modulation

music-theory://counterpoint

Species counterpoint rules, consonance/dissonance, motion types

music-theory://modes-scales

Diatonic modes, minor scale variants, pentatonic/blues, genre guide

music-theory://orchestration

Instrument ranges, GM program numbers, texture types

music-theory://rhythm-patterns

Time signatures, MIDI duration reference, genre grooves

music-theory://voice-leading

Forbidden parallels, voicing strategies, non-chord tones

MCP clients that support resource reading can pass these to the AI as context, enabling theory-aware composition.

Example Composition

const composition = {
  bpm: 120,
  timeSignature: { numerator: 4, denominator: 4 },
  tracks: [
    {
      name: "Piano",
      instrument: 0,
      notes: [
        { chord: "Cmaj7", beat: 1, duration: "2", velocity: 90 },
        { chord: "Am7",   beat: 3, duration: "2", velocity: 90 },
        { chord: "Fmaj7", beat: 5, duration: "2", velocity: 90 },
        { chord: "G7",    beat: 7, duration: "2", velocity: 90 }
      ]
    },
    {
      name: "Melody",
      instrument: 0,
      notes: [
        { pitch: "E4", beat: 1, duration: "4", velocity: 100 },
        { pitch: "G4", beat: 2, duration: "4", velocity: 100 },
        { pitch: "A4", beat: 3, duration: "2", velocity: 110 }
      ]
    }
  ]
};

Demo

The prompt below generates an 8-bar melodic minor choral piece:

Create an 8-bar choral piece in a slightly minor, melodic scale.

https://github.com/user-attachments/assets/e20ebef0-fdbf-4e72-910d-41b94183f9d9

melodic_minor_chorus.mid

Build & Development

npm install

# Full build (UI + server)
npm run build

# Build steps individually
npm run build:ui     # Vite — builds the MCP App preview HTML
npm run build:server # tsc — compiles TypeScript server

# Deploy to Cloudflare Workers
npm run deploy

# Run tests
npm test
npm run test:coverage

Dependencies

Package

Purpose

@modelcontextprotocol/sdk

MCP server implementation (stdio & HTTP transports)

@modelcontextprotocol/ext-apps

MCP Apps extension — interactive UI in conversation

midi-writer-js

MIDI file generation

@tonejs/midi

MIDI parsing (preview UI)

soundfont-player

Audio playback in preview UI

zod

Input schema validation

This server cannot be installed

A
license - permissive license
-
quality - not tested
B
maintenance

How are these scores calculated?

Maintenance

–Maintainers
–Response time
–Release cycle
–Releases (12mo)
Commit activity

Resources

Unclaimed servers have limited discoverability.

Looking for Admin?

If you are the server author, to access and configure the admin panel.

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/tubone24/midi-mcp-server'

If you have feedback or need assistance with the MCP directory API, please join our Discord server