OSC MCP Server

MCP Server for controlling a Behringer X-Air XR18 digital mixer via Open Sound Control (OSC) protocol.

Features

• 18 input channels with fader, mute, EQ (4 bands), and bus sends

• 6 buses (monitor/aux) with fader and mute

• Main LR output control

• 4 FX slots with send level and mute

• Symbolic naming — refer to channels and buses by name (e.g. "Kick", "Drummer") instead of numbers

• dB-to-float conversion — work in dB, the server handles the XR18's non-linear fader scale

• Persistent connection — the server remembers the last mixer IP across sessions

• Raw OSC escape hatch for any unsupported command

Related MCP server: osc-bridge

Prerequisites

• Python >= 3.11

• uv package manager

• A Behringer XR18 (or other X-Air mixer) on your local network

Installation

git clone https://github.com/darkwings/OSC_MCP.git
cd OSC_MCP
uv sync

Running the Server

# Run via stdio (used by MCP clients)
uv run osc-mcp

# Or use the MCP inspector for interactive testing
uv run mcp dev src/osc_mcp/server.py

Adding to an MCP Client

Claude Desktop

The easiest way is to use the built-in install command:

uv run mcp install src/osc_mcp/server.py --name "OSC Mixer"

Alternatively, open Claude Desktop and go to Settings > Developer > Edit Config, then add:

{
  "mcpServers": {
    "osc-mcp": {
      "command": "uv",
      "args": ["run", "--directory", "/absolute/path/to/OSC_MCP", "osc-mcp"]
    }
  }
}

Restart Claude Desktop after saving.

Claude Code

claude mcp add osc-mcp -- uv run --directory /absolute/path/to/OSC_MCP osc-mcp

Or manually add to .mcp.json or ~/.claude/mcp.json:

{
  "mcpServers": {
    "osc-mcp": {
      "command": "uv",
      "args": ["run", "--directory", "/absolute/path/to/OSC_MCP", "osc-mcp"]
    }
  }
}

Cursor

Go to Settings > MCP Servers > Add Server and use:

• Type: stdio

• Command: uv run --directory /absolute/path/to/OSC_MCP osc-mcp

Generic MCP Client

Any MCP-compatible client can connect using the stdio transport:

uv run --directory /absolute/path/to/OSC_MCP osc-mcp

Replace /absolute/path/to/OSC_MCP with the actual path where you cloned the repository.

Usage

Once the server is running in your MCP client:

1. Connect: connect_mixer("192.168.1.1") — the IP is saved for future sessions

2. Name your channels: assign_channel_name(1, "Kick"), assign_bus_name(2, "Drummer")

3. Control: set_channel_fader("Kick", -5), set_channel_send_to_bus("Kick", "Drummer", -10)

On subsequent sessions, the server automatically reconnects to the last known mixer IP. If the mixer is unreachable (e.g. different network), the agent is prompted to ask for the new IP.

Available Tools

Running Tests

uv run pytest

License

Apache License 2.0