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 Impertio-Studio/Three.js-Claude-Skill-Package --skill threejs-impl-shadowsgit clone --depth 1 https://github.com/Impertio-Studio/Three.js-Claude-Skill-PackageWrote 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/impertio-studio/three.js-claude-skill-package/threejs-impl-shadows)<a href="https://agentmods.dev/skills/impertio-studio/three.js-claude-skill-package/threejs-impl-shadows"><img src="https://agentmods.dev/badge/skills/impertio-studio/three.js-claude-skill-package/threejs-impl-shadows/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/impertio-studio/three.js-claude-skill-package/threejs-impl-shadows"><img src="https://agentmods.dev/badge/skills/impertio-studio/three.js-claude-skill-package/threejs-impl-shadows.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00118 | $0.02674 |
| Opus 5.5 | $0.00047 | $0.01070 |
| Sonnet 5.5 | $0.00024 | $0.00535 |
| Haiku 4.5 | $0.00012 | $0.00267 |
Grade A, and why
threejs-impl-shadows 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 1mo 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 — 318 lines — stays where its author put it; the contents beside it link to each section on GitHub.
threejs-impl-shadows
Quick Reference
Three-Step Shadow Opt-In
Shadows in Three.js require THREE explicit opt-in steps. Missing ANY step results in no shadows.
import * as THREE from 'three';
// Step 1: Enable shadow maps on the renderer
renderer.shadowMap.enabled = true;
renderer.shadowMap.type = THREE.PCFSoftShadowMap;
// Step 2: Enable shadow casting on the light
light.castShadow = true;
// Step 3: Enable per-mesh shadow behavior
mesh.castShadow = true; // this mesh casts shadows
ground.receiveShadow = true; // this mesh receives shadows
Shadow Map Types
| Type | Constant | Quality | Cost | Supports .radius |
|---|---|---|---|---|
| Basic | THREE.BasicShadowMap |
Hard edges, aliased | Lowest | No |
| PCF | THREE.PCFShadowMap |
Slightly softened | Moderate | No |
| PCF Soft | THREE.PCFSoftShadowMap |
Soft penumbra | Higher | No (ignores it) |
| VSM | THREE.VSMShadowMap |
Gaussian blur | Moderate | Yes |
- Default in r160+:
THREE.PCFShadowMap - PCFSoftShadowMap: best general-purpose choice; IGNORES the
shadow.radiusproperty - VSMShadowMap: supports
shadow.radiusandshadow.blurSamplesbut can exhibit light bleeding on thin geometry
Critical Warnings
NEVER forget any of the three opt-in steps -- missing even one produces zero shadows with no error message.
NEVER leave the DirectionalLight shadow camera frustum at default size -- it is almost ALWAYS wrong for your scene. ALWAYS configure it manually.
NEVER use more than 1-2 shadow-casting PointLights -- each PointLight shadow renders 6 cubemap faces per frame.
ALWAYS set shadow.mapSize to power-of-two values (512, 1024, 2048, 4096).
ALWAYS add light.target to the scene when repositioning a DirectionalLight or SpotLight target.
Shadow Map Types -- Detailed Comparison
BasicShadowMap
No filtering applied. Produces hard, aliased shadow edges. Use ONLY for debugging or stylized rendering where hard shadows are intentional.
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.
- 1mo ago First seen · 318 lines · 118 tokens per session scan A a97f772a19aa
threejs-impl-shadows is a skill published in the GitHub repository Impertio-Studio/Three.js-Claude-Skill-Package (23 stars, last pushed 3mo ago), licensed MIT. It adds 118 tokens to every session and 2,674 once invoked, about $0.0005 per session on Opus 5.5. 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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