Grandorgue Mcp

io.github.sandraschiPublished by GitHub account sandraschiv0.3.0Updated Oct 24, 2026

GrandOrgue pipe organ simulator MCP server - MIDI bridge, organ control, sample set management, m...

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Overview

AI-generated overview

MCP server that bridges an AI assistant to the GrandOrgue pipe organ simulator over MIDI, letting it control stops, pistons, manuals and swell pedals.

What you can do
Control the organ: operate stops, pistons, manuals and swell pedals through MIDI from an AI agent or the bundled web console, replacing the simulator's built-in GUI with a React dashboard.
When to use it
Useful if you run the GrandOrgue pipe organ simulator and want an AI agent or a browser-based console to drive its stops and manuals instead of the stock interface.
Requirements
Runs locally as a stdio process. Needs GrandOrgue installed, at least one sample set, uv for Python dependencies, and Node.js 20+ for the web console; the optional web mode uses ports 11010 (backend) and 11011 (frontend). GrandOrgue must be configured to use the virtual MIDI ports.
Before you install
It sends MIDI control to a running GrandOrgue instance, so commands change the live instrument state. The web console exposes local HTTP and WebSocket endpoints on ports 11010 and 11011. No credentials are declared.

Installation

In SourceWeft

  1. Open Grandorgue Mcp in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

GrandOrgue MCP

[Stars] [License] [CI] [Python] [FastMCP] [MIDI] [Fleet SOTA] [React]

Modern Organ Console — a free control surface for the GrandOrgue pipe organ simulator.

GrandOrgue MCP gives GrandOrgue a beautiful, responsive web console + AI-agent-capable backend. It connects to GrandOrgue via MIDI and replaces its aging wxWidgets GUI with a modern React dashboard. Every stop, piston, manual, and swell pedal is controllable from any browser — or from an AI agent via MCP tools.

Built for the GrandOrgue community with gratitude for decades of free organ simulation. This is our contribution back — a modern console layer that works with any existing GrandOrgue installation and sample set.

Contents

Quick Start

Prerequisites

  • GrandOrgue installed (Windows / Linux / macOS)
  • uv for Python dependency management
  • Node.js 20+ for the web console

One-Command Setup

powershell
# Install backend depsjust install
# Install frontend depsjust install-web
# Launch everything (backend + frontend + browser)just web

The backend starts on port 11010 (HTTP mode), the frontend on port 11011.

Claude Desktop (stdio)

The server defaults to stdio transport for MCP clients. Build the bundle with just mcpb and install dist/grandorgue-mcp-vX.Y.Z.mcpb in Claude Desktop. The webapp uses HTTP mode (MCP_TRANSPORT=http), which just web sets automatically.

Manual Start

powershell
# Terminal 1 — Backenduv run grandorgue-mcp
# Terminal 2 — Frontend (opens browser)cd web_sota && bun run dev

First-Time Setup

  1. Install GrandOrgue from GitHub Releases
  2. Install at least one free sample set (see docs/SAMPLE_SETS.md)
  3. Start the MCP server (uv run grandorgue-mcp)
  4. Open the web console at http://127.0.0.1:11011
  5. From the Dashboard, click Start GrandOrgue then Connect MIDI
  6. GrandOrgue must be configured to use the virtual MIDI ports (see docs/MIDI_SETUP.md)

Ports

PortService
11010Backend (HTTP mode) — FastMCP 3.4 (/mcp) + FastAPI REST + WebSocket /ws
11011Frontend — Vite React SPA, proxies /api → 11010

Tech Stack

LayerTechnology
BackendPython 3.12+, FastMCP 3.4, FastAPI, uvicorn
MIDI Bridgemido + python-rtmidi (virtual ports)
Audio EngineGrandOrgue C++ (untouched — MIDI control only)
FrontendReact 18, TypeScript, Tailwind CSS, Vite (Bun), Zustand, Lucide, react-router-dom, framer-motion, react-markdown
LintingRuff (Python), Biome (TypeScript)
Testingpytest + Playwright e2e

License

MIT — free for the GrandOrgue community, forever.

Source: README.md at commit 0f7af48

Tools

0
SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

1
  1. v0.3.0LatestSep 16, 2026

Score

50% of the applicable checks met

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  • Reached in the last 30 days25 pts

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  • Auth declared10 pts

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  • Tools listed15 pts

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  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts