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 majiayu000/spellbook --skill app-ui-designgit clone --depth 1 https://github.com/majiayu000/spellbookWrote 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/majiayu000/spellbook/app-ui-design)<a href="https://agentmods.dev/skills/majiayu000/spellbook/app-ui-design"><img src="https://agentmods.dev/badge/skills/majiayu000/spellbook/app-ui-design/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/majiayu000/spellbook/app-ui-design"><img src="https://agentmods.dev/badge/skills/majiayu000/spellbook/app-ui-design.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- 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 | $0.00054 | $0.02877 |
| Opus 5.5 | $0.00022 | $0.01151 |
| Sonnet 5.5 | $0.00011 | $0.00575 |
| Haiku 4.5 | $0.00005 | $0.00288 |
Grade A, and why
app-ui-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 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 — 418 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mobile App UI Design
Expert guidance for designing beautiful, accessible, and platform-native mobile app interfaces following 2025 best practices.
Core Philosophy
- User-First Design — Prioritize user needs, behaviors, and mental models over aesthetics
- Platform Consistency — Follow iOS HIG and Android Material Design guidelines
- Accessibility as Foundation — Design for all users from the start, not as an afterthought
- Emotional Intelligence — Create interfaces that users emotionally connect with
- Performance-Conscious — Beautiful design that doesn't sacrifice app performance
Hard Rules (Must Follow)
These rules are mandatory. Violating them means the skill is not working correctly.
Accessibility First
All designs must meet WCAG 2.2 AA standards. Accessibility is not optional.
❌ FORBIDDEN:
- Color contrast below 4.5:1 for text
- Touch targets smaller than 44×44pt (iOS) or 48×48dp (Android)
- Information conveyed by color alone
- Missing alternative text for images
- Non-keyboard-navigable interfaces
✅ REQUIRED:
- Minimum 4.5:1 contrast ratio for normal text
- Minimum 3:1 contrast ratio for large text (18pt+)
- Touch targets: 44×44pt (iOS) / 48×48dp (Android)
- Support for Dynamic Type / Font Scaling
- VoiceOver (iOS) / TalkBack (Android) compatibility
- Clear focus indicators for keyboard navigation
Platform Guidelines Adherence
Follow platform-specific design guidelines. Do not mix iOS and Android patterns.
❌ FORBIDDEN:
- Using Android-style FAB on iOS
- Using iOS-style bottom sheets on Android without adaptation
- Mixing platform navigation patterns
- Ignoring platform typography (SF Pro vs Roboto)
✅ REQUIRED:
iOS (Human Interface Guidelines):
- Use SF Pro font family
- Tab bar at bottom for primary navigation
- Push navigation with back chevron
- Standard iOS controls (UIKit/SwiftUI)
Android (Material Design 3):
- Use Roboto font family
- Bottom navigation bar or navigation drawer
- Material components with ripple effects
- Follow Material You dynamic theming
What ships with it
6 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 · 418 lines · 54 tokens per session scan A 152eeae1d51a
app-ui-design is a skill published in the GitHub repository majiayu000/spellbook (288 stars, last pushed 2d ago), licensed MIT. It adds 54 tokens to every session and 2,877 once invoked, about $0.0002 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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