Borrowing it
Nothing to install: this file belongs to YankielDBC2/codex-skills-library. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/YankielDBC2/codex-skills-library/main/.agents/skills/mobile-density-ui-system-v2/SKILL.mdgit clone --depth 1 https://github.com/YankielDBC2/codex-skills-libraryWrote 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/yankieldbc2/codex-skills-library/mobile-density-ui-system-v2)<a href="https://agentmods.dev/skills/yankieldbc2/codex-skills-library/mobile-density-ui-system-v2"><img src="https://agentmods.dev/badge/skills/yankieldbc2/codex-skills-library/mobile-density-ui-system-v2.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 5.1 | $0.00037 | $0.00430 |
| Opus 5 | $0.00018 | $0.00215 |
| Sonnet 5 | $0.00007 | $0.00086 |
| Haiku 4.5 | $0.00004 | $0.00043 |
Grade A, and why
mobile-density-ui-system-v2 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 8d 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
Mobile Density UI System v2
Goal
Make mobile layouts compact, scannable, and conversion-friendly without sacrificing readability or touch comfort.
When to use
Use when mobile pages feel too tall, cards are oversized, every section becomes one column, product/service grids create too much scroll, or important content is buried.
Workflow
- Inspect the real content types: products, services, thumbnails, stats, categories, testimonials, CTAs, or form blocks.
- Decide whether each mobile section needs one column, two columns, horizontal scroll, compact cards, accordions, or progressive disclosure.
- Use two-column mobile grids for small product/service/category cards when content and tap targets remain readable.
- Reduce oversized headings, py-20/py-24 spacing, huge images, and card padding that create unnecessary scroll.
- Keep primary CTAs visible and avoid burying purchase or contact actions below decorative content.
- Use CSS grid, flex, container queries, or project utilities according to the existing style system.
- Test breakpoints around 360, 390, 430, 768, 1024, and desktop when possible.
Quality bar
- Check responsive behavior in browser/devtools or by inspecting CSS classes and breakpoints.
- Run available lint/type/build checks.
- Confirm no horizontal overflow or clipped content.
Validation
- Mobile shows more useful content per screen without feeling cramped.
- Tap targets remain usable and text remains readable.
- Two-column mobile grids are used where they improve browsing, not everywhere blindly.
- Hero and section heights are proportional to content.
Final response
- Report mobile density choices and any breakpoints manually verified.
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.
- 8d ago First seen · 52 lines · 37 tokens per session scan A 8be978a93765
mobile-density-ui-system-v2 is a skill published in the GitHub repository YankielDBC2/codex-skills-library (10 stars, last pushed 1mo ago), licensed MIT. It adds 37 tokens to every session and 430 once invoked, about $0.0002 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 2026-08-31.
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