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- Updated
- February 15, 2026Feb 15
- Published
- in 2024
Sample — Text dump of actions and observations with frame. · swipe
At a glance
A library: other mods need it
Runs on Fabric
For Minecraft 1.21.3
Client only — no need to install it on the server
Latest version — 1.6.1+1.21.3 from February 15, 2026
Requires Fabric API
Where it's neededGame versions1.21.3
In gamerequiredOn servernot needed
Install in the game only; not needed on the server
Minecraft Input/Output (MCio)
MCio mod | mcio_ctrl | Documentation | Discord
MCio is a Fabric mod that exposes a network interface to Minecraft for AI research. It accepts keyboard/mouse input and sends back video frames and game state over ZeroMQ.
Features
- Python library (mcio_ctrl) with Gymnasium environments
- Faster than real-time performance (>13x on an M3 laptop)
- Works with performance mods like Sodium
- Supports resource packs for varied training environments
- Connect/reconnect agents without restarting Minecraft
- Decoupled ZMQ protocol for easy integration
- Synchronous mode for fast training
- Asynchronous mode for real-time human/AI interaction
- Headless mode with GPU acceleration
- VPT and STEVE-1 support on modern Minecraft with Sodium
Links
FAQ
How to install MCio?
Install Fabric for your Minecraft version, download MCio for the same version and loader, put the file into the mods folder and launch the game with the loader profile.
Which Minecraft versions does MCio support?
MCio has builds for Minecraft 1.21.3.
Is MCio needed on the server?
Client only — no need to install it on the server
License and source
MIT Licensefree to use and share with credit to the author
