ReaperMCP: compose, mix and master in REAPER with an agent

Making music in a DAW comes with plenty of grunt work beyond the ideas: creating a row of tracks, routing sends, loading the same FX chain, checking loudness before export. ReaperMCP connects REAPER to an agent so those jobs take one sentence, and the agent can even write the notes and CC data itself. It talks to a Lua script running inside REAPER through files on disk, all local. It had about 80 stars as of 2026-10-06 and is still niche.

What it does

• 181 tools across the workflow: transport, tracks, MIDI notes and CC, markers and regions, tempo maps, envelopes, sends and routing, FX parameters and presets.
• Composition helpers: create_drum_pattern uses step-sequencer notation, create_chord_progression turns "Cm7, Fm7, Bb7, Eb" into voiced MIDI, and load_loops scans a sample pack and builds tracks by BPM and key.
• Mix and master: engine_mix and engine_master apply 35 style profiles, with one-call setups for drum buses, vocal chains, parallel compression and sidechains.
• Post-production QC: analyze_loudness measures LUFS against streaming or broadcast targets; analyze_clipping, analyze_silence and analyze_region_qc find clipping, silence and click candidates.

Who it’s for

• REAPER users making electronic music or arrangements who want the project skeleton and FX chains set up first.
• Podcast and video post people who want loudness checks and silence or click detection across many files.
• Musicians curious about AI-assisted composition who don’t want their sessions in the cloud.

Setup

You need REAPER 7+ and Python 3.10+. The repo ships one-click installers (install.bat on Windows, install.sh on macOS and Linux) that also configure Claude Desktop and auto-load the Lua script when REAPER starts. To install by hand:

pip install xdarkzx-reaper-mcp

Then add "reaper": {"command": "reaper-mcp"} to your client config and load reaper_scripts/reaper_mcp_server.lua from the repo in REAPER (the PyPI package doesn’t include it).

Our take

Most audio servers stop at playback or transcription. ReaperMCP goes deep into the DAW, from composition to mastering, and the author is upfront about limits such as skipping CC reads. That’s why it’s worth a look. Caveats: 181 tools strain context and smaller models, so the README suggests REAPER_MCP_PROFILE subsets like mixing or analysis. It can delete tracks, wipe MIDI and run project ReaScripts through script_run, so save first. REAPER must be open with the Lua script running. The project started in April 2026 and is still moving fast. Licensed Apache-2.0.