Reaper Daemon — Claude Code MCP server: mix REAPER with an agent
A file bridge that lets an AI agent drive your open REAPER session: read the project, change FX, write automation and measure each move.
Open on GitHubWhat Reaper Daemon does
The agent writes a JSON command into a folder. A Lua script running inside REAPER executes it and writes a JSON result back. No socket, no port, no extension. Anything that can touch files works with it, from Claude to Codex or Cursor, and an optional stdio MCP server, reaper_mcp.py, publishes the same bridge as tools. The setup is pure Lua inside REAPER plus plain Python 3 outside, with no pip packages for the core.
In practice scan_fx lists every plugin and its parameters, values are set in real units such as "-2.5 dB", and automation gets written from commands. verify_change records a track before and after an edit and reports what shifted in the audio. Every move lands inside a REAPER undo block, so Ctrl+Z takes back whatever the agent did.
Rendering and audio capture stay switched off until you allow them, and every measurement depends on them, verify_change included: run python3 setup/install.py --allow-audio-writes. Saving the project, touching REAPER preferences and executing Lua each have a separate switch. The Claude plugin can walk you through setup, but the repository still has to be cloned on the machine running REAPER first.
What it helps with
- list the plugins on a bus and their current settings
- cut mud around 300 Hz on a bass track from the chat
- match a vocal level by LUFS and confirm it with a measurement
- turn an audio item into drum MIDI
- compare spectrum and dynamics before and after a mix edit
Example prompts for the agent
- Scan the plugins on the bass track and show me their parameters
- Reduce the mud near 300 Hz on the bass and check what changed in the audio
How to install Reaper Daemon
Install
The MCP registry has no launch command for it: see the repository README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Reaper Daemon
How do I install Reaper Daemon in Claude Code?
Clone the repository on the computer that runs REAPER: git clone https://github.com/wretcher207/reaper-daemon.git, then cd reaper-daemon and python3 setup/install.py. Restart REAPER and confirm the bridge answers with python3 reaperd.py status.
What does Reaper Daemon do?
It hands an agent control over your open REAPER session: project reads, FX parameter changes, automation, tracks, MIDI and rendering. You can then measure the result with verify_change.
Why does verify_change fail or return nothing?
Rendering and capture are disabled unless you enable them, and all measurements rely on them. Turn them on with python3 setup/install.py --allow-audio-writes.
