Reaper Daemon

Reaper Daemon is a REAPER MCP server and file bridge for driving REAPER from an AI agent, including mixing your session with Claude or any other agent. No network socket, no port, no extensions.

The agent drops a JSON command file in a folder. A Lua script inside REAPER runs it and writes a JSON result back. That's the whole protocol. It works with Claude Code, Codex, Cursor, or anything else that can read and write files, and an optional stdio MCP server, reaper_mcp.py, exposes the same bridge as tools for Claude Desktop and any other MCP client.

macOS, Windows, Linux. Pure Lua inside REAPER, plain Python 3 outside, no pip packages. Every change runs inside a REAPER undo block, so Ctrl+Z reverts anything an agent does.

Install

git clone https://github.com/wretcher207/reaper-daemon.git
cd reaper-daemon
python3 setup/install.py

Restart REAPER, then check the bridge is alive:

python3 reaperd.py status

Prefer ReaPack, or want to load the bridge by hand? See docs/install.md.

Mix with an AI agent

Point Claude, or any agent talking to Reaper Daemon, at your open REAPER session and ask it to work on the mix. It reads every plugin and parameter with scan_fx, sets FX values in real units like "-2.5 dB", and writes automation. verify_change captures the track before and after a move and reports what changed in the audio, so you are not taking its word for it. Every move sits inside a REAPER undo block, and your ears make the call.

Example prompts:

• "The bass is muddy around 300 Hz, pull it down."
• "Bring the vocal down so it sits with the mix instead of on top."
• "Tune the bass until its LUFS is down 3 dB."
• "What plugins are on the drum bus, and what are they set to?"

See MCP server for setup and Verify for what the measurements do and do not prove.

What it does

The bridge knows nothing about any specific plugin or drum library. Agents discover what a project contains and act on it by name.

Three ways to talk to it

CLI. One Python entry point for everything an agent does.

python3 reaperd.py send commands/examples/get_context.json --wait
python3 reaperd.py shred --track argent-l --bars-file riff.txt --seed 101

MCP server. reaper_mcp.py wraps the bridge as tools over stdio. Ask Claude Desktop to "measure the drums" and it does.

Daemon Console. A chat panel docked inside REAPER, backed by a headless Claude Code session that always knows which track you have selected.

Docs

Agents should read AGENTS.md, CLAUDE.md, and bridge/command_schema.md. Two bundled skills, arrangement-midi and drum-humanize, cover MIDI composition and drum humanization.

Security

Any process that can write to inbox/ can drive REAPER. Keep the bridge folder local and off shared drives. Details in docs/security.md.

License

MIT. See LICENSE.

Keyboard performance setup, MIDI/controller tests and template saving are documented in the performance workflow.