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 cosmicstack-labs/mercury-agent-skills --skill responsive-designgit clone --depth 1 https://github.com/cosmicstack-labs/mercury-agent-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/cosmicstack-labs/mercury-agent-skills/responsive-design)<a href="https://agentmods.dev/skills/cosmicstack-labs/mercury-agent-skills/responsive-design"><img src="https://agentmods.dev/badge/skills/cosmicstack-labs/mercury-agent-skills/responsive-design.svg" alt="Measured on agentmods" 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 | $0.00022 | $0.00583 |
| Opus 5 | $0.00011 | $0.00292 |
| Sonnet 5 | $0.00004 | $0.00117 |
| Haiku 4.5 | $0.00002 | $0.00058 |
Grade A, and why
responsive-design 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 4d 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
Responsive Design
Modern responsive design patterns using mobile-first methodology, CSS Grid, Flexbox, and container queries.
Mobile-First Approach
/* Base styles = Mobile */
.container {
padding: 1rem;
display: flex;
flex-direction: column;
gap: 1rem;
}
/* Tablet */
@media (min-width: 768px) {
.container {
flex-direction: row;
flex-wrap: wrap;
padding: 2rem;
}
}
/* Desktop */
@media (min-width: 1024px) {
.container {
max-width: 1200px;
margin: 0 auto;
padding: 3rem;
}
}
Container Queries
/* Instead of viewport queries, query the container */
.card-container {
container-type: inline-size;
container-name: card;
}
@container card (min-width: 400px) {
.card {
display: grid;
grid-template-columns: 200px 1fr;
}
}
@container card (max-width: 399px) {
.card {
display: flex;
flex-direction: column;
}
}
Fluid Typography
/* Fluid type scale using clamp() */
:root {
--text-sm: clamp(0.875rem, 0.8rem + 0.25vw, 1rem);
--text-base: clamp(1rem, 0.9rem + 0.5vw, 1.25rem);
--text-lg: clamp(1.25rem, 1rem + 1vw, 1.75rem);
--text-xl: clamp(1.5rem, 1rem + 2vw, 2.5rem);
}
Common Mistakes
- Starting with desktop: Always design mobile-first. It's easier to add than remove.
- Relying only on media queries: Use
min-widthnotmax-width. Use container queries for reusable components. - Ignoring touch targets: Minimum 44x44px tap targets. No hover-dependent interactions on mobile.
- Fixed widths and heights: Use
min-height,max-width, and intrinsic sizing. - Not testing on real devices: Emulators aren't enough. Test on actual phones and tablets.
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.
- 4d ago First seen · 90 lines · 22 tokens per session scan A 03fab8cd4c90
responsive-design is a skill published in the GitHub repository cosmicstack-labs/mercury-agent-skills (471 stars, last pushed 13d ago), licensed MIT. It adds 22 tokens to every session and 583 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 2026-09-03.
Other skills, from other repositories
frontend-ui-engineering
Builds production-quality, accessible, responsive user-facing UIs. Use when building or modifying interfaces and pages, creating components, implementing layouts, meeting WCAG accessibility requirements, managing state, or when the output needs to look and feel production-quality rather than AI-generated.
playground
Creates interactive HTML playgrounds — self-contained single-file explorers that let users configure something visually through controls, see a live preview, and copy out a prompt. Use when the user asks to make a playground, explorer, or interactive tool for a topic.
frontend-design
Guidance for distinctive, intentional visual design when building new UI or reshaping an existing one. Helps with aesthetic direction, typography, and making choices that don't read as templated defaults.
baseline-ui
Quickly deslop UI code by fixing spacing, hierarchy, typography, and small layout issues. Use when the interface needs a fast cleanup or polish pass.
web-design-engineer
Build or redesign polished browser-rendered visual artifacts with HTML/CSS/JavaScript/React: pages, dashboards, prototypes, slide decks, animations, UI mockups, and data visualizations. Use for visual front-end creation, design-system exploration, design critique, or explicit browser acceptance / QA of a web artifact.…
frontend-design
A guide for building polished web interfaces such as pages, dashboards, applications, posters, and reusable React or Vue components. It covers visual direction, layout, typography, colors, animation, accessibility, and working HTML, CSS, or JavaScript code.