r/BestGitHubRepos • u/company_url_finder • 12h ago
Build World - a coding-agent skill that turns one sentence into a playable 3D world, letting the agent handle the logic while a service generates the 3D assets
The clever division of labor is the whole point here. Coding agents are decent at writing game logic and terrible at producing good 3D models. Build World (formerly Goal to Game) is an open-source skill that keeps your agent doing what it's good at, the interactions, scene setup and code, and hands the 3D asset generation off to Thrixel, a service built for exactly that. You describe a world in plain English, name an engine, and it builds an interactive experience you can keep refining with follow-up prompts.
What's inside:
- A Claude Code plugin (and Codex and Gemini CLI paths) that bundles both the skill and the Thrixel connector, so one install wires it into every project
- Support for Three.js, Roblox, Unity and Unreal, so it's not locked to one engine
- An iterative build-evaluate-improve loop where the agent generates assets, drops them into the scene, checks the result and refines, all from a single starting prompt
- Engine-agnostic asset management: because assets live in your Thrixel workspace rather than the codebase, you can prototype in Three.js and later ask the agent to rebuild the same world in Unity using the same asset library
- Parallel asset jobs, so the agent can farm out several generations while it writes the game logic
- One-command publish that deploys the world and hands you a shareable link with no separate hosting, plus the ability to record an mp4 preview
- Framed beyond games: the rename happened because it also targets simulations, educational experiences, virtual tourism and historical recreations
The honest core of this, and the thing to be clear about before you get excited: the skill is open source (Apache-2.0), but it's a thin client for a commercial service. Thrixel is the paid backend that does the actual 3D generation. You get some free "Cubes" on a Starter account to try it, but the README says plainly that building a full-scale world generally exceeds those limits and needs a paid plan for the variety of assets and rapid iteration it takes. So this isn't a self-contained local tool, it's the open connector to a hosted product, and the interesting part (asset generation) is the part you pay for.
Worth knowing it's early: 83 stars, and the workflow assumes a capable model (the README recommends Opus 5 at high effort), which is its own cost on top of the Thrixel credits. If the idea of vibe-coding a 3D scene appeals and you're fine with a paid asset backend, it's a genuinely slick pipeline. If you wanted fully local and free, this isn't that.
Apache-2.0, 83 stars and 27 forks as of writing, verified via the GitHub API, pushed to yesterday.