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 curiositech/some_claude_skills --skill color-contrast-auditorgit clone --depth 1 https://github.com/curiositech/some_claude_skillsWrote 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/curiositech/some_claude_skills/color-contrast-auditor)<a href="https://agentmods.dev/skills/curiositech/some_claude_skills/color-contrast-auditor"><img src="https://agentmods.dev/badge/skills/curiositech/some_claude_skills/color-contrast-auditor/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/curiositech/some_claude_skills/color-contrast-auditor"><img src="https://agentmods.dev/badge/skills/curiositech/some_claude_skills/color-contrast-auditor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 372 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 375 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00116 | $0.03286 |
| Opus 5 | $0.00058 | $0.01643 |
| Sonnet 5 | $0.00023 | $0.00657 |
| Haiku 4.5 | $0.00012 | $0.00329 |
Grade A, and why
color-contrast-auditor 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 — 429 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Color Contrast Auditor
Detects color contrast violations that make text unreadable and provides WCAG-compliant fixes. Uses both mathematical contrast ratio analysis and perceptual evaluation via vision capabilities.
When to Use
Activate on:
- Screenshots of websites/apps with suspected contrast issues
- CSS/Tailwind files for color audit
- "I can't read this" or "this is hard to see"
- Pre-launch accessibility checks
- Design system color validation
NOT for:
- Choosing brand colors (use
web-design-expert) - Color harmony/aesthetics (use
color-theory-palette-harmony-expert) - Non-visual accessibility (screen readers, keyboard nav)
WCAG 2.1 Contrast Requirements
Minimum Ratios (AA - Required)
| Text Type | Minimum Ratio | Example |
|---|---|---|
| Normal text (<24px, <18.66px bold) | 4.5:1 | Body copy, labels, buttons |
| Large text (≥24px or ≥18.66px bold) | 3:1 | Headlines, hero text |
| UI components (borders, icons) | 3:1 | Form inputs, icons, focus rings |
| Graphical objects | 3:1 | Charts, infographics |
Enhanced Ratios (AAA - Recommended)
| Text Type | Minimum Ratio |
|---|---|
| Normal text | 7:1 |
| Large text | 4.5:1 |
Non-Text Elements
| Element | Requirement |
|---|---|
| Focus indicators | 3:1 against adjacent colors |
| Form field borders | 3:1 against background |
| Icons conveying meaning | 3:1 against background |
| Disabled elements | No requirement (but consider UX) |
Contrast Ratio Formula
Contrast Ratio = (L1 + 0.05) / (L2 + 0.05)
Where L1 = lighter color's relative luminance
L2 = darker color's relative luminance
Calculating Relative Luminance
function relativeLuminance(r, g, b) {
// Convert 0-255 to 0-1
let [rs, gs, bs] = [r, g, b].map(c => c / 255);
// Apply gamma correction
const gamma = c => c <= 0.03928
? c / 12.92
: Math.pow((c + 0.055) / 1.055, 2.4);
const [R, G, B] = [rs, gs, bs].map(gamma);
// Weighted sum (human eye sensitivity)
return 0.2126 * R + 0.7152 * G + 0.0722 * B;
}
function contrastRatio(color1, color2) {
const l1 = relativeLuminance(...color1);
const l2 = relativeLuminance(...color2);
const lighter = Math.max(l1, l2);
const darker = Math.min(l1, l2);
return (lighter + 0.05) / (darker + 0.05);
}
What ships with it
2 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.
- 12d ago First seen · 429 lines · 116 tokens per session scan A ca60f6ea0201
color-contrast-auditor is a skill published in the GitHub repository curiositech/some_claude_skills (219 stars, last pushed 5d ago), licensed MIT. It adds 116 tokens to every session and 3,286 once invoked, about $0.0006 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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