Gearboy
A Game Boy emulator with a debugger and a built-in MCP server: the agent controls execution, reads memory and inspects hardware state
Medium risk
We rate an entry medium when the tool runs code, makes network calls or reads project files. Check what exactly it does before installing.
Why this level
- The agent controls execution and reads memory of the emulated system
- It runs a local emulator process with network or stdio access
Install
Manual install
brew install --cask drhelius/geardome/gearboyFor macOS; for other systems download a build from releases. Launching with --mcp-stdio enables the MCP server.
This is third-party code. Review the repository files before installing.
What it does
Gearboy is an accurate Game Boy, Game Boy Color and Super Game Boy emulator with a full debugger and a built-in MCP server. Over MCP the agent gets tools for execution control, memory reading and hardware state inspection, which is handy for debugging and retro-platform development. The server starts with the emulator in stdio or HTTP mode. The app runs on Windows, macOS, Linux and BSD, and also as a RetroArch core.
Who it is for. For developers and retro-platform enthusiasts who want agent-assisted Game Boy debugging.
Good fit when
- You need agent-assisted debugging of a Game Boy game or program
- You need to read memory and control emulator execution from an agent
- You need to inspect the retro platform's hardware state
Not a fit when
- You do not need the Game Boy platform
- You need a plain emulator without agent integration
Example request
Set a breakpoint and show what happens in memory on this game frameLimitations
The MCP server is built into the emulator and started by its flags, with no separate package. Work happens against the emulated system, and you need your own ROMs to run. The agent's abilities are limited to Gearboy's debugger tools.
How to disable. Launch the emulator without the MCP flag, or uninstall the app via your package manager and remove the server entry from your client config.
MCP
- Transport
- stdio, http
- Authentication
- not required
Security check
- The agent controls execution and reads memory of the emulated system
- It runs a local emulator process with network or stdio access
README in short
The README describes Gearboy as an accurate cross-platform Game Boy, Game Boy Color and Super Game Boy emulator with a full debugger and a built-in MCP server for agent-assisted debugging. The MCP server starts with the --mcp-stdio or --mcp-http flags and exposes execution control, memory reading and hardware state inspection. The app installs from releases, via brew and other packages, and also runs as a RetroArch core. A separate agent skill is available. GPL-3.0 licensed.
FAQ
Do I need a separate MCP server?
No, the server is built into the emulator and started with the --mcp-stdio or --mcp-http flag.
What is available to the agent?
Debugger tools: execution control, memory reading and hardware state inspection.
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