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 littlejs-apigit 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/littlejs-api)<a href="https://agentmods.dev/skills/killedbyapixel/littlejs-ai/littlejs-api"><img src="https://agentmods.dev/badge/skills/killedbyapixel/littlejs-ai/littlejs-api/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/littlejs-api"><img src="https://agentmods.dev/badge/skills/killedbyapixel/littlejs-ai/littlejs-api.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 | $0.00074 | $0.00332 |
| Opus 5 | $0.00037 | $0.00166 |
| Sonnet 5 | $0.00015 | $0.00066 |
| Haiku 4.5 | $0.00007 | $0.00033 |
Grade A, and why
littlejs-api 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 10d 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.
What it actually says
littlejs-api
The curated LittleJS API reference ships with this plugin at:
${CLAUDE_SKILL_DIR}/../../reference.md
It is ~900 lines / 48KB — do NOT read the whole file into context. Grep it for the symbol you need and read only the surrounding lines:
- Look up one symbol: grep for the symbol name (e.g.
ParticleEmitter,drawTile,tileCollisionTest) and read ~20 lines around the first hit — entries are one-line signatures with a trailing//comment, grouped in sections. - Broader area (e.g. "what sound functions exist?"): grep for the section keyword (
Audio,Input,Drawing,Particles,Tile Collision) and skim that section only. - If a symbol is NOT in the reference, verify against the engine build itself before concluding it exists: grep
${CLAUDE_SKILL_DIR}/../../dist/littlejs.jsfor it. Trust the engine source over memory.
For engine conventions and pitfalls (argument-order traps, per-frame vs per-second units, naming rules), use the littlejs-conventions skill instead — this skill is only for exact API lookup.
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.
- 10d ago First seen · 19 lines · 74 tokens per session scan A 0f3bd8a89f61
littlejs-api is a skill published in the GitHub repository KilledByAPixel/LittleJS-AI (77 stars, last pushed 4d ago), licensed MIT. It adds 74 tokens to every session and 332 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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