Gauntlet Gamesmith by GlassBox AI LabsDownload for MacFrom prompt to playable, with the full loop exposed.
Generate browser games through a visible build-and-critique loop, showing every trace, cost, and eval behind the final result.
No babysitting.
Set a spending ceiling and walk away. It stops when the critic passes your game, the rounds run out, or the money does.
It studies the real thing first.
Name the game yours should feel like. It gathers stills, clips, and sources before writing a line.
It criticises itself.
A second agent, with no memory of building, plays your game and scores it. The notes go back in.
Nothing is hidden.
Every prompt, command, helper, and cost estimate is on screen while it works.
Every round is saved.
Play any earlier version. Publish the one you like.
The loop, in one drag.
Round 1A later run0.40failround 1 · verdict.json
Round 1 failed. Every finding went into round 2. That is the whole idea.
See how a run worksDownload for MacMade here. Played here.
Publish from the app. Anyone can play it in a browser, no account.
The arcade is liveGet it
Apple menu, About This Mac. If the chip says Apple, take the first one. Mac only, v0.1.1.
macOS blocks it the first time. Right-click, Open, confirm. Once.
Three things you need
A Claude or ChatGPT subscription
Runs Claude Code or Codex. Installs it for you if needed.
Node.js LTS
Previews the games.
Git
Snapshots every round.
Everything stays on your machine. No account, no server.
Costs shown in the app are estimates. It runs on the subscription you already pay for, with your own login.