reaper-orchestra 0.1.2

Orchestra MCP server for REAPER

Orchestra

Orchestra is a lightweight MCP bridge for REAPER. It lets AI agents call DAW operations through a Python MCP server and a Lua script running inside REAPER.

What is Orchestra

Orchestra connects three parts:

1. REAPER-side Lua scripts (execute DAW actions)
2. Python MCP server (registers tools and handles MCP calls)
3. File-based IPC bridge (~/.orchestra/inbox, outbox, archive)

The design goal is practical AI-assisted music editing, not only one-shot generation.

Installation

Prerequisites:

• uv
• REAPER

Install uv (official standalone installer):

# macOS / Linux
curl -LsSf https://astral.sh/uv/install.sh | sh

# Windows (PowerShell)
powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

Install Orchestra from PyPI as a uv-managed tool:

uv tool install reaper-orchestra
orch --help

If orch is not found in your shell, add uv's tool bin directory to PATH:

uv tool update-shell

Quick Start (5 min)

1. Install REAPER scripts:

orch scripts "<REAPER Scripts directory>"

This command copies files into:

• <REAPER Scripts directory>/rfhits/orchestra

2. In REAPER, run orchestra_loader.lua.
3. Add Orchestra to your MCP client config (see MCP Client Configuration). The client launches orch launch automatically.
4. Call tools from your MCP client.
5. To stop the REAPER side loop, run orchestra_stop.lua in REAPER.

REAPER Integration

End-to-end flow:

1. MCP tool (Python) calls bridge.call_reaper("module.method", params)
2. Request JSON is written to ~/.orchestra/inbox
3. REAPER main loop dispatches and executes
4. Reply JSON is written to ~/.orchestra/outbox and archived

MCP Client Configuration

For Claude Desktop, edit this MCP config file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\\Claude\\claude_desktop_config.json

To use command: "orch" directly in MCP config, make sure orch is installed and available on PATH (for example: uv tool install reaper-orchestra).

Add Orchestra under mcpServers:

{
  "mcpServers": {
    "orchestra": {
      "command": "orch",
      "args": ["launch"]
    }
  }
}

Why uv helps here: it manages the environment and keeps the CLI launch path simple (orch).

Core Capabilities

• Project info, tempo/time-signature control
• Track CRUD, color, mute/solo, parent-child folder relation
• Item CRUD, split/merge, color, length
• Take add/list/activate
• Marker create/list/update/delete
• Audio insert/render (seconds/measures)
• MIDI insert/render (seconds/measures)

Limitations

• Not a full replacement for manual mixing decisions
• No full automatic “concept-level” local audio regeneration yet
• FX-chain and automation workflows are still being expanded

Demos and Ecosystem

Video demos:

• when agent touches DAW (reaper) - YouTube
• continue and arrange MIDI in reaper via agent & MCP - YouTube
• 当 Agent 遇见 DAW(Reaper) - 哔哩哔哩
• agent 接入 reaper 进行 MIDI 续写和编曲 - 哔哩哔哩

Related MCP music projects and tools:

• awesome-music-mcp: https://github.com/Music-MCP/awesome-music-mcp

Contributing / License

• Issues and pull requests are welcome.
• See LICENSE for licensing terms.