Genex's desktop app is free, and it is for making a game with AI. The app is open source under the MIT license, which means you can use it, change it, and share it. It runs on a Mac with an Apple chip, and on Linux. Windows is listed as coming soon. The project says it is early, and to expect rough edges.
The page says you do not buy a new AI bill to start. The page says the app builds with a Claude or ChatGPT subscription you already have, or with a model running on your own computer. That local model goes through Ollama or Bonsai. You pick a model for each job: the one that plans, the ones that build, and the ones that judge.
You do not paste in a key. Claude Code, and ChatGPT's coding tool Codex, sign in on their own. The app never sees those logins. Your plan's limits still apply. If you hit them, the app does not switch over to charging you for each call.
Right now the games are Three.js games. Three.js is a tool for 3D that runs in a browser. The game stays as ordinary files on your computer. You can pack those files and put them on any website, or publish them on genex.games. Unity and Unreal, the big game engines, are coming later, as is a phone app written in C++. Those are not in the app today.
The page's example is a basketball game in an empty arena, with purple seats and a shot clock. You dribble, sprint, and time your shots. The film shows that court beside the chat.
For the pictures and models, Blender on your own computer can make 3D without leaving the machine. Meshy, Tripo, and ElevenLabs, tools for models, characters, and voice, are available through a Genex plugin. That plugin is the only paid part, and you can skip it.
There is also a switch that stays off until you turn it on. The app's tools, skills, and prompts live in a folder it can edit. Before each change it saves a copy. A blind judge compares the result. If the new version will not start, it puts the old one back on its own. They call this experimental.
The page does not show a bad build being caught.
Editorial
I make games alone. The part I would use is the ordinary files. I need a folder I can open, change, and put on a site I already have. That is what this page offers, and it does not wait on Unity.
The plan I already pay for is the other half. A new bill, or a key I have to paste in, is one more thing to handle before the first level exists. Signing in with Claude or ChatGPT, and stopping when the plan runs out, keeps the cost where it already is.
I would leave the self-edit switch off. A tool that rewrites its own instructions can help when I am the only one working, and it can also change the tool while I am trying to finish a scene. They start that switch off. I would not count on the rollback, because the page does not show a build that failed to start and then came back.