Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add KilledByAPixel/LittleJS-AI --skill atlas-shape-artgit clone --depth 1 https://github.com/KilledByAPixel/LittleJS-AIWrote 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/killedbyapixel/littlejs-ai/atlas-shape-art)<a href="https://agentmods.dev/skills/killedbyapixel/littlejs-ai/atlas-shape-art"><img src="https://agentmods.dev/badge/skills/killedbyapixel/littlejs-ai/atlas-shape-art/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/killedbyapixel/littlejs-ai/atlas-shape-art"><img src="https://agentmods.dev/badge/skills/killedbyapixel/littlejs-ai/atlas-shape-art.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00073 | $0.01452 |
| Opus 5 | $0.00036 | $0.00726 |
| Sonnet 5 | $0.00015 | $0.00290 |
| Haiku 4.5 | $0.00007 | $0.00145 |
Grade A, and why
atlas-shape-art 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.
atlas-shape-art
For shape-based LittleJS games, bake the 16 built-in white icons ONCE with initDefaultAtlas() and draw every entity as a per-instance tinted drawTile — instead of drawCircle/drawEllipse/drawPoly. The shapes already exist in templates/textureGenerator.js; you do not hand-roll a canvas or a star-point array.
Core win: one shared atlas → every sprite is a single quad in one unbroken WebGL batch, recolorable to any hue for free, zero external assets.
When to use
- New game whose look is geometric/abstract/neon/puzzle/arcade, or has lots of round/polygon entities (orbs, gems, bubbles, asteroids, stars, particles-as-entities).
- Retrofit: an existing game calling many
drawCircle/drawEllipse/drawPoly/drawRegularPolyper frame and the rendering is a hot spot.
Not for: representational art (a specific character, a detailed prop) — draw that as a custom sprite with drawToTexture. A handful of shapes drawn once is fine as-is; this is for many instances or a shape-driven art style.
Why it's faster (don't skip — agents get this wrong)
drawCircle → drawEllipse → drawRegularPoly tessellates a 32-sided polygon (glCircleSides = 32) and pushes ~32 verts per call through the untextured-poly path. drawPoly / drawRegularPoly are the same path. A tinted drawTile is one quad (2 triangles) and all atlas drawTile calls collapse into a single batched draw.
Common misconception: "drawCircle batches in WebGL too, 300 is trivial." It batches, but at ~16× the vertices of a quad and on a separate path from your textured sprites, breaking the uniform batch. drawRect is the exception — it is already drawTile(pos, size, undefined, color), a single quad, so rects are NOT the bottleneck. The win is round/polygon shapes and keeping everything in one texture batch.
The 16 shapes (tiles 0–15)
circle glow ring roundSquare · triangle diamond pentagon hexagon · heart droplet plus arrow · spark star burst bolt
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.
- 12d ago First seen · 84 lines · 73 tokens per session scan A 53e18027a9a2
atlas-shape-art is a skill published in the GitHub repository KilledByAPixel/LittleJS-AI (78 stars, last pushed 6d ago), licensed MIT. It adds 73 tokens to every session and 1,452 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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