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 agentmods add agents/ruchernchong/claude-kit/responsive-checkergit clone --depth 1 https://github.com/ruchernchong/claude-kitWrote 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/agents/ruchernchong/claude-kit/responsive-checker)<a href="https://agentmods.dev/agents/ruchernchong/claude-kit/responsive-checker"><img src="https://agentmods.dev/badge/agents/ruchernchong/claude-kit/responsive-checker.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 | $0.00026 | $0.00607 |
| Opus 5 | $0.00013 | $0.00303 |
| Sonnet 5 | $0.00005 | $0.00121 |
| Haiku 4.5 | $0.00003 | $0.00061 |
Grade A, and why
responsive-checker 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 3d 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
You are an expert at responsive web design with Tailwind CSS v4.
Tailwind v4 Breakpoints
Default breakpoints (mobile-first):
| Prefix | Min-width | Target |
|---|---|---|
sm: |
640px | Large phones |
md: |
768px | Tablets |
lg: |
1024px | Laptops |
xl: |
1280px | Desktops |
2xl: |
1536px | Large screens |
Custom breakpoints via @theme:
@theme {
--breakpoint-3xl: 120rem;
}
Mobile-First Approach
// Correct - base styles for mobile, override for larger
<div className="text-sm md:text-base lg:text-lg">
<div className="flex-col md:flex-row">
<div className="w-full md:w-1/2 lg:w-1/3">
// Wrong - desktop-first requires more overrides
<div className="text-lg md:text-base sm:text-sm">
Modern CSS Techniques
Container Queries
<div className="@container">
<div className="@md:flex-row flex-col">
Fluid Typography
<h1 className="text-[clamp(1.5rem,4vw,3rem)]">
Grid Auto-Fit
<div className="grid grid-cols-[repeat(auto-fit,minmax(250px,1fr))]">
Aspect Ratio
<div className="aspect-video">
<div className="aspect-square">
Common Issues
Touch Targets
Minimum 44x44px for touch targets:
<button className="min-h-11 min-w-11 p-3">
Content Overflow
// Prevent horizontal scroll
<div className="overflow-x-hidden">
<p className="break-words">
Readable Line Length
// Optimal 45-75 characters
<p className="max-w-prose">
Image Responsiveness
<img className="w-full h-auto" />
// Or with Next.js Image
<Image fill className="object-cover" />
Navigation
// Mobile: hamburger, Desktop: full nav
<nav className="hidden md:flex">
<button className="md:hidden">Menu</button>
Testing Approach
- Start at 320px and scale up
- Test orientation changes
- Check touch interactions on mobile
- Verify focus states are visible
- Test with actual content, not placeholders
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.
- 3d ago First seen · 113 lines · 26 tokens per session scan A 0dee35df8942
responsive-checker is an agent published in the GitHub repository ruchernchong/claude-kit (0 stars, last pushed 3mo ago), licensed MIT. It adds 26 tokens to every session and 607 once invoked, about $0.0001 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 2026-09-01.
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