Reaper Reapy

A Python application for controlling REAPER Digital Audio Workstation (DAW) using the MCP(Model context protocol).

Features

• Track Management: Create, rename, and color tracks
• FX Management: Add, remove, and control effect parameters
• Project Control: Set tempo, manage regions and markers
• Master Track Control: Volume, pan, mute, and solo operations
• MIDI Operations: Create items, add/get notes, clear items with musical positioning
• Audio Item Operations: Insert, duplicate, modify with enhanced positioning support
• Dual Position Format: Support both time (seconds) and measure:beat notation
• Reliable Duplication: Uses REAPER's built-in commands for accurate item copying
• MCP Integration: Model Context Protocol server for AI assistant control

Status

• Checked on Linux: Yes
• MCP HTTP Mode: Supported for parameters

Requirements

• Python 3.7+
• REAPER DAW
• python-reapy Python module
• mcp[cli] package for MCP server
• Internet connection (for downloading sample audio file)

Installation

1. Install REAPER if you haven't already
2. Enable reapy server via REAPER scripting add reaper_side_enable_server.py to reaper actions and run it inside reaper studio
3. Install the package:

   # From PyPI
   pip install reaper_reapy_mcp
   
   # From GitHub repository
   pip install git+https://github.com/wegitor/reaper-reapy-mcp.git
   

4. Enable python in REAPER

The wheel package includes all necessary dependencies and can be used in other Python projects that need REAPER integration. The project uses pyproject.toml for modern Python packaging configuration, which provides better dependency management and build system configuration.

Sample Audio File

The application uses a sample MP3 file for testing audio operations. The file will be automatically downloaded when needed from:

https://www2.cs.uic.edu/~i101/SoundFiles/StarWars3.mp3

This is a short Star Wars theme clip that's commonly used for testing audio applications.

Running the Server

You can run the server using uv directly:

uv --directory <project_path> run -m reaper_reapy_mcp

For the current directory and http MCP mode:

uv --directory . run -m reaper_reapy_mcp --mode http

For example, on Windows:

uv --directory C:\path\to\reaper_reapy_mcp run -m reaper_reapy_mcp

Or using the Python module directly after installation:

python -m reaper_reapy_mcp

HTTP Mode

Run the server in HTTP mode with default settings:

python -m reaper_reapy_mcp --mode http

Run with custom host and port:

python -m reaper_reapy_mcp --mode http --http-host example_host --http-port 3958

Use the MCP inspector to test the tools:

test_mcp.bat

Available MCP tools:

Track Management

• test_connection: Verify connection to REAPER
• create_track: Create a new track
• rename_track: Rename an existing track
• set_track_color: Set track color
• get_track_color: Get track color
• get_track_count: Get number of tracks in project
• get_track_list: Get list of all tracks with their properties

FX Management

• add_fx: Add an FX to a track
• remove_fx: Remove an FX from a track
• set_fx_param: Set FX parameter value
• get_fx_param: Get FX parameter value
• get_fx_param_list: Get list of FX parameters
• get_fx_list: Get list of FX on a track
• get_available_fx_list: Get list of available FX plugins
• toggle_fx: Toggle FX enable/disable state

Project Control

• set_tempo: Set project tempo
• get_tempo: Get current tempo
• get_time_signature: Get current time signature
• set_project_time_signature: Set project default time signature
• set_time_signature: Set time signature at position
• create_region: Create a region
• delete_region: Delete a region
• create_marker: Create a marker
• delete_marker: Delete a marker
• render_project: Render project to audio file

Master Track

• get_master_track: Get master track information
• set_master_volume: Set master track volume
• set_master_pan: Set master track pan
• toggle_master_mute: Toggle master track mute
• toggle_master_solo: Toggle master track solo

MIDI Operations

• create_midi_item: Create an empty MIDI item on a track
  • Supports both time (seconds) and measure:beat positioning
• add_midi_note: Add a MIDI note to a MIDI item
• add_midi_notes: Add multiple MIDI notes at once
• get_midi_notes: Get all MIDI notes from a MIDI item
• clear_midi_item: Clear all MIDI notes from a MIDI item

Audio Item Operations

• insert_audio_item: Insert an audio file as a media item
  • Supports both time (seconds) and measure:beat positioning
• duplicate_item: Duplicate an existing item (MIDI or audio)
  • Uses REAPER's built-in duplication for reliable copying
  • Supports both time (seconds) and measure:beat positioning
• get_item_properties: Get properties of a media item
• set_item_position: Set the position of a media item
  • Supports both time (seconds) and measure:beat positioning
• set_item_length: Set the length of a media item
• delete_item: Delete a media item
• get_items_in_time_range: Get items within a time range
  • Supports both time (seconds) and measure:beat positioning

Item ID System

All item operations use a sequential index system (0..n) for item identification. This makes it easier to work with items in scripts and automation:

• Item IDs are zero-based indices
• Each track maintains its own sequence of item indices
• Indices are stable until items are deleted or reordered
• All item operations (MIDI, audio, properties) use the same indexing system

Position Format Support

Many MCP tools now support dual position formats for enhanced musical workflow:

Time Format (seconds)

{
  "start_time": 15.5,
  "new_time": 30.0
}

Measure:Beat Format

{
  "start_measure": "3:2,500",
  "new_measure": "5:1,000"
}

Format: "measure:beat,fraction" where:

• measure: 1-based measure number
• beat: 1-based beat number
• fraction: milliseconds (000-999) representing fraction of a beat
• Example: "4:2,500" = measure 4, beat 2, half beat (500ms)

Tools Supporting Both Formats:

• create_midi_item - position via start_time OR start_measure
• insert_audio_item - position via start_time OR start_measure
• duplicate_item - position via new_time OR new_measure
• set_item_position - position via new_time OR new_measure
• get_items_in_time_range - range via time OR measure parameters

Claude configuration (with uv run):

{
    "mcpServers": {
        "reaper-reapy-mcp": {
            "type": "stdio",
            "command": "uv",
            "args": [
                "--directory",
                "<path to folder>",
                "run",
                "-m",
                "reaper_reapy_mcp"
            ]
        }
    }
}

Claude configuration direct:

{
    "mcpServers": {
        "reaper-reapy-mcp": {
            "type": "stdio",
            "command": "python",
            "args": [
                "-m",
                "reaper_reapy_mcp"
            ]
        }
    }
}

or

{
    "mcpServers": {
        "reaper-reapy-mcp": {
            "type": "stdio",
            "command": "python",
            "args": [
                "<path to folder>\\src\\reaper_reapy_mcp.py"
            ]
        }
    }
}

Contributing

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

License

This project is licensed under the MIT License - see the LICENSE file for details.