Introduction

Thrixel, a 3D generation startup founded by University of Chicago computer scientist Rana Hanocka,

with $3M in inception funding and a pitch aimed straight at game builders who now work alongside coding agents: generated 3D models that come out as named, editable parts, not one fused mesh.

It's a closed, hosted service. You can use it today in the browser at thrixel.com, through its API and MCP server, or through Build World, an Apache-2.0 skill on GitHub that lets Claude Code, Codex, Cursor or Gemini CLI build a playable game in Three.js, Unity, Roblox or Unreal Engine while Thrixel makes every asset.

What Thrixel actually generates

Per the funding announcement, Thrixel's part-aware architecture builds assets from individually named components with a logical hierarchy, so an agent can find "the door" or "the propeller" and move it with code. Under the hood it chains vision language models, agentic pipelines, diffusion and optimization, each mapped to a step of the modeling pipeline, so you can run the whole flow or only one step.

What you get in the web app:

  • Text or image to 3D, refined with follow-up prompts.
  • Full object hierarchy, with parts grouped and labeled.
  • Version history with branching, so you can fork any earlier edit.
  • An Auto engine (added 6 October), which
    and photoreal image-to-3D to the Sculptor engine.

Thrixel told one user on X that it's

, usable from the web app or via API with your coding agent. It hasn't posted a public price list yet.

Build World: one sentence to a playable game

Build World (previously called Goal to Game) splits the job in two. Your coding agent writes the game logic, sets up the scene and playtests it in a loop. Thrixel generates, textures and slims down every model it asks for, in parallel with the code.

The engine pages spell out what that means in practice:

  • Roblox: each named part imports as its own MeshPart, so scripts can open a door or spin a propeller. Models are scaled in studs against the player character, static parts are merged to cut draw calls, and uploads go through Roblox Open Cloud. Scripts sync to Studio as Luau through Rojo.
  • Unity: models land as FBX in your Assets folder, moving parts like wheels stay separate GameObjects, material slots survive grouping, and triangle counts can be cut to your budget. WebGL builds can be published to a shareable link on thrixel.world.
  • Three.js and Unreal are supported targets too; you name the engine in your prompt.

To try it with Claude Code (you'll need uv installed), the README setup is:

uvx thrixel-mcp@latest login
claude plugin marketplace add thrixel/build-world
claude plugin install thrixel@thrixel

Then describe the game and name the engine. This is Thrixel's own Unity example:

/thrixel:build-world build a hovercraft racing game in Unity through a desert canyon, with ancient ruins, boost gates, and moving obstacles

Unity projects also need the Unity Editor and Unity CLI installed; the skill's setup flow walks through connecting them.

Who's behind it

Hanocka runs a 3D AI research lab at UChicago and

"to put that research directly into people's hands." Backers include Sierra Ventures, MFV Partners, Harper Court Ventures and Z5 Capital, plus graphics researcher Jon Barron and former EA executive Matt Bilbey. Early users quoted on the site include Look North World, the studio founded by Bungie co-founder Alex Seropian, and Jakkal Games.

Why it matters for game teams

Most AI 3D tools still hand back one lump of geometry, which is fine for a background prop and useless for anything that has to move. Named parts are what make a generated asset scriptable: an agent can't animate a door it can't find. Thrixel is betting that as more prototypes get built by coding agents, the asset generator has to speak in parts and hierarchies, not just polygons. It lands the same week as Scenario's Opus 5.5 3D and Dreamlands 1.0, both also chasing editable output.

The caveats are the usual ones. Pricing is credit-based and not yet public, the models aren't open, and agent-built prototypes still need a human pass on gameplay, collision and performance before anything ships. Check Thrixel's terms before using assets commercially.

Conclusion

If you're already prototyping with Claude Code, Codex or Cursor, Build World is the quickest way to see whether named-part assets save you real time. Install the skill, ask for one small game in the engine you actually ship on, and open the result to see how much cleanup the models need.

—Titus