Tiny World Builder is a browser-based 3D voxel editor for creating, sculpting, exploring, saving, remixing, exporting, and sharing small block-based worlds. It is used by people who want to build terrain and scenes with objects such as homes, paths, crops, and animals. Its catalogue add-ons support work with the editor.
Borrowing it
Nothing to install: this file belongs to jasonkneen/tiny-world-builder. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/jasonkneen/tiny-world-builder/main/.agents/skills/threejs-primitive-reconstructor/SKILL.mdgit clone --depth 1 https://github.com/jasonkneen/tiny-world-builderWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/jasonkneen/tiny-world-builder/threejs-primitive-reconstructor)<a href="https://agentmods.dev/skills/jasonkneen/tiny-world-builder/threejs-primitive-reconstructor"><img src="https://agentmods.dev/badge/skills/jasonkneen/tiny-world-builder/threejs-primitive-reconstructor.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00081 | $0.01036 |
| Opus 5 | $0.00041 | $0.00518 |
| Sonnet 5 | $0.00016 | $0.00207 |
| Haiku 4.5 | $0.00008 | $0.00104 |
Grade A, and why
threejs-primitive-reconstructor scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
The source is not reproduced here
Licensed AGPL-3.0
The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.
What ships with it
4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 7d ago First seen · 78 lines · 81 tokens per session scan A fcb0a1791844
threejs-primitive-reconstructor is a skill published in the GitHub repository jasonkneen/tiny-world-builder (1,554 stars, last pushed today), licensed AGPL-3.0. It adds 81 tokens to every session and 1,036 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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