SimConnect MCP server

SimConnect MCP Server

<!-- mcp-name: io.github.robin24/simconnect-mcp -->

An MCP (Model Context Protocol) server that connects AI coding agents to Microsoft Flight Simulator via SimConnect. This server is built for add-on development — full read/write access to SimVars, L-vars, events, calculator code execution, and embedded documentation.

What It Does

• Read/write any SimVar — altitude, heading, speed, autopilot settings, engine parameters, and 1,080+ more from a comprehensive built-in catalog, with unit selection and honest failures on a rejected write
• Read/write L-vars — aircraft-specific local variables used by add-on developers (Fenix A320, FlyByWire A32NX, PMDG, etc.), including live enumeration of what the loaded aircraft has actually registered
• PMDG 777 and 737 NG3 native SDK support — direct access to all aircraft data fields and control events via the PMDG SDK Client Data Areas, plus CDU screen reading with colors/formatting
• Trigger events — toggle switches, set autopilot modes, control lights, fire custom MobiFlight events
• Execute RPN calculator code — run arbitrary Reverse Polish Notation code directly in the sim
• Search and discover variables — searchable catalogs of SimVars, events, and aircraft-specific L-vars with human-readable names and valid values
• Facilities lookup — nearby airports sorted by distance and detail lookup for a specific airport, waypoint, NDB or VOR by ICAO identifier, read directly from SimConnect's facility subscription
• Flight and scenario tools — load and save .FLT flights, load a .PLN flight plan, and spawn an AI aircraft or object, for scripting test scenarios instead of setting them up by hand
• Embedded documentation — SimConnect reference docs served as MCP resources, available offline
• Aircraft-specific catalogs — pre-built variable databases with panel groupings, display names, and value descriptions. Ships with 1,607 PMDG 777 variables (777-200LR/200F/300ER/F) and 1,861 PMDG 737 NG3 variables (-600/700/800/900 incl. BBJ/BDSF/BCF).
• HubHop integration — search the MobiFlight HubHop community preset database directly as an MCP tool, or use the built-in client to generate and extend L-var catalogs for any supported aircraft

Prerequisites

• Microsoft Flight Simulator (MSFS 2020 or 2024) running on the same machine
• uv — provides uvx, which fetches the server and its Python runtime for you
• MobiFlight WASM Module (optional, for L-var support) — install in your MSFS Community folder. Download from MobiFlight

Installation

Published on PyPI as simconnect-mcp, and listed in the MCP Registry as io.github.robin24/simconnect-mcp.

Once uv is installed, no separate install step is needed — uvx fetches and runs the server on demand:

uvx simconnect-mcp

That starts the server on stdio, which is what an MCP client does for you. Run it by hand only to check that it starts; press Ctrl+C to stop.

To pin a version, use uvx simconnect-mcp@1.0.1.

From source (for development)

git clone https://github.com/robin24/simconnect-mcp.git
cd simconnect-mcp

# Creates the virtual environment and installs the dev group too
uv sync

Configuring as an MCP Server

Claude Code

Via CLI:

claude mcp add --transport stdio simconnect -- uvx simconnect-mcp

Or to make it available across all projects:

Shortened. The full README is on GitHub.