reaper-mcp-server

MCP.Pizza Chef: dschuler36

This reads your REAPER project files straight off disk and reports back on them: tempo, tracks, effects chains, and a full measurement of every audio clip covering peak level, clipping, loudness against streaming targets, stereo width and phase problems. It can also list the plugins you already own, so you can ask which of them suits a sound you have in mind. Nothing is written back. It cannot edit or save your project, REAPER does not even need to be open, and no account or key is required.

Data
Other

Use This MCP server To

Check whether any of my vocal takes are clipping Find out if my mix is too loud for streaming Spot phase problems across my drum tracks before mixdown List every reverb plugin I already have installed Summarise the tempo, tracks and effects in a project

README

Reaper MCP Server

This is an MCP server that connects Reaper projects to an MCP client like Claude Desktop, enabling you to ask questions about your projects and get comprehensive audio analysis for mixing feedback.

Tools

Project Discovery & Parsing

  • find_reaper_projects: Finds all Reaper projects in the directory you specified in the config.
  • parse_reaper_project: Parses a Reaper project file (.RPP) and returns detailed information including tempo, tracks, FX chains, and audio items.

These tools work in tandem. When you ask Claude a question about a specific Reaper project, it will use the find_reaper_projects tool to find the project, then use the parse_reaper_project tool to parse the project and answer your question.

Installed FX Discovery

  • list_installed_fx(plugin_type=None, search_query=None): Lists all installed FX/plugins available in Reaper.

    Parameters:

    • plugin_type (optional): Filter by plugin type (VST2, VST3, AU, JS, CLAP)
    • search_query (optional): Search plugins by name, manufacturer, or type

    Returns: List of installed plugins including:

    • Plugin name
    • Plugin type (VST2, VST3, AU, JS, CLAP)
    • File path
    • Manufacturer (when available)

    Example Questions:

    • "What synth plugins do I have installed?"
    • "Show me all my Waves plugins"
    • "I'm looking for a warbly synth. What options do I have from my already installed plugins?"
    • "List all my VST3 plugins"
    • "Do I have any reverb plugins?"
    • "What iZotope plugins do I have?"
    • "Show me all my Audio Unit plugins"

    Note: This tool scans your Reaper plugin cache files. If you recently installed new plugins and haven't scanned them in Reaper yet, they won't appear in the results. Make sure to open Reaper and let it scan for new plugins first.

Audio Analysis

  • analyze_audio_files(project_path, track_filter=None): Analyzes all audio files in a Reaper project for mixing feedback.

    Parameters:

    • project_path (required): Path to the .RPP project file
    • track_filter (optional): Filter tracks by name (e.g., "Vocal" to analyze only vocal tracks)

    Returns: Comprehensive audio analysis including:

    • Level Analysis: Peak levels, RMS, clipping detection
    • Frequency Analysis: Spectral content, energy distribution across frequency bands
    • Stereo Imaging: Stereo width, phase coherence, mono compatibility
    • Dynamic Range & Loudness: LUFS (loudness standards), true peak, crest factor

    Example Questions:

    • "Analyze all audio in my Rock Song project"
    • "Check the vocal tracks for clipping"
    • "Is my mix too loud for streaming platforms?"
    • "Are there any phase issues in my drum tracks?"

    Warning Thresholds:

    • Peak > -0.3 dBFS: Risk of clipping
    • Clipping detected: Digital distortion present
    • Excessive low frequency energy (> -6 dB): Muddy mix
    • Phase coherence < 0.5: Phase cancellation issues
    • LUFS > -8: Too loud for streaming (Spotify target: -14 LUFS)
    • Crest factor < 6 dB: Possibly over-compressed

To see all data structures parsed from projects, check out the src/reaper_mcp_server/reaper_dataclasses.py file.

Setup

  1. Install Dependencies

    uv venv
    source .venv/bin/activate
    
    uv pip install .
  2. Configure Claude Desktop

    • Follow the instructions to configure Claude Desktop for use with a custom MCP server
    • Find the sample config in setup/claude_desktop_config.json
    • Update the following paths in the config:
      • Your uv installation path
      • Your Reaper project directory
      • This server's directory
  3. Launch and Configure

    • Open Claude Desktop
    • Click the '+' icon on the chat box
    • Click on 'Connectors' and you should see the 'reaper' connector enabled

    Claude Desktop Connectors

  4. Ask Away!

    • Ask questions about your Reaper project
    • Always include the name of the specific Reaper project you're asking about
    • You can expand the tool boxes to see the raw project data being passed to Claude Claude Desktop Tools

reaper-mcp-server FAQ

Does REAPER need to be running?
No. It reads your saved project files and audio directly from disk, so REAPER can be closed the whole time.
Can it change or damage my project?
No, and that is a genuine strength here. All four of its tools only read. It cannot add tracks, move clips, apply effects, or save anything over your work.
Do I need an account or a key?
No. Everything runs on your own machine against your own files, with no outside service involved.
Can I use this to get mixing feedback?
Yes — it measures peak level, clipping, loudness, stereo width and phase for each clip, and flags the ones that fall outside safe ranges for streaming.
Which apps does it work in?
It is documented for Claude Desktop and works with any assistant that can start a local command-line server.
How hard is setup?
Developer-level. You clone the project, install it with uv, then hand-edit a configuration file with the paths to uv, the project folder, and your REAPER projects.
Why can it not find one of my projects?
It only matches files ending in a capital .RPP, and only inside the one projects folder you named in the configuration.
Is it actively maintained?
It is a small hobby project. The last code change was February 2026, roughly six months ago, so expect slow fixes.