Every creature is compiled from one JSON spec. No mesh files, no downloaded art packs, no photogrammetry. The worked example that ships with this repo, example/wolf.json, is 2,211 vertices and 31 joints written out by the engine from plain text.

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Quick start

bash setup.sh                              # deps + red/green ruler calibration
node engine/cli.js example/wolf.json out/wolf.glb

setup.sh must print calibrate OK before you trust anything else: it builds one spec that has to pass and two that have to be blocked, so you know the rulers separate good from bad on your machine.

To run the full text-to-creature session, point an agent at MANUAL.md and let it read cards/ in order — 00_START → 01_LOW → 02_MID → 03_HIGH → 04_SHIP.

Driving it harder

What is actually in here

How it works

flowchart LR
    A[Order<br/>one sentence] --> B[Interview<br/>≤ 2 questions] --> C[Silhouette<br/>brief] --> D[LOW<br/>design free]
    D --> E{Gate 1<br/>RECOGNISED}
    E -->|fail| D
    E -->|pass| F{Gate 2<br/>PUNCHIER}
    F -->|reverted| D
    F -->|pass| G[MID<br/>all parts] --> H[HIGH<br/>colour + anims] --> I[SHIP<br/>stamp · deliver]

The two gates

Neither gate is self-graded. The session that designed the creature is the worst possible judge of whether it reads, because it already knows what it drew. So the silhouettes go to a context-free reader agent that has never seen the order, and the only question is "what is this?"

Gate 1 is RECOGNISED: all four views have to land. Gate 2 is PUNCHIER: a new round may only make the silhouette bolder than the last one — a round that tames the shape is reverted, even if it is "more correct". LOW's deliverable is an exaggerated silhouette, not an accurate one.

The engine floors

The compiler talks in three registers, and they mean different things:

Floors are not style opinions. They are the failures that survive review and ship broken: a body that renders in hard facets, a horn that hovers a centimetre off the skull, a right thigh collapsed to 40% depth by mirrored skinning.

What gets measured

Every round renders these four views, reduces them to masks, and computes the numbers the design card declared a target for — width over height, mass thirds, torso depth contrast, leg fraction, silhouette turn count, zigzag alignment, and IoU against the previous round as a regression guard. The 24px thumbnail is what the blind reader actually sees; if it does not read at 24px, it does not read.

The doctrine in one paragraph

Head-to-head experiments showed the model designs BOLDLY when left free, and every attempt to teach it design upfront made the output tamer — so this harness ships a clean painter and a strict inspector. The creation side gets only the order, the engine syntax, and a short pit-map of engine-local traps; ALL quality control lives in gates read by context-free reader agents, never self-graded. Form beats obedience, everywhere.

Honesty about limits

• Isolated-part blind reads misfire on dome-plus-hanging-tube heads. Elephants and birds get read as something else when the head is shown alone; put the same head back on the body and it reads fine. Trust the whole-body read when the two disagree.
• Cost is only measured on two bosses, at roughly 4.4M tokens each. Minions and NPCs should be cheaper, but nobody has measured them, so treat the preset budgets in harness/presets/ as estimates rather than data.
• part_attachment and mirror_distortion are new in 1.2.0. Specs authored against an older version may now be blocked. That is usually the checker being right, but it is a breaking change, not a silent improvement.
• The example wolf ships two animations, not three. Card 03 asks for idle, move and attack; example/wolf.json has idle and move. Copy it for structure, not for animation coverage.
• The engine has zero dependencies; the tooling does not. Every render and measure tool drives headless Chromium through playwright. If playwright will not install, you can still compile creatures — you just cannot measure them, and the gates are the point.

Scripts

Requirements

Node 18+ and Python 3.9+. setup.sh installs three, playwright, numpy, pillow and scipy, then runs the calibration self-check. The engine alone needs nothing but Node; the dependencies are for the measuring and render tools.

Security

Short-lived local servers used by the render tools bind to 127.0.0.1 only, and Chromium runs with its OS sandbox enabled. The Gobkit submission key in harness/gobkit.json is public by design — it authorises posting to the community wall and nothing else. Details and reporting: SECURITY.md.

Licence

MIT — see LICENSE. One third-party component is bundled (harness/assets/three-bundle.js, three.js, MIT); attributions for it and for everything setup.sh installs are in THIRD-PARTY-NOTICES.md.

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About

Gobkit: AI-native 3D infrastructure for agents and vibe coders. Stream game-ready 3D assets straight into your workflows via API. Agent-friendly. Studio-quality. Built by a team of artists and engineers.

Author: Ariescar | Alsomindtech

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