Borrowing it
Nothing to install: this file belongs to chama-x/GroundRules. 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/chama-x/GroundRules/master/.agents/archive/v3/skill_hig-doctor/skills/hig-foundations/SKILL.mdgit clone --depth 1 https://github.com/chama-x/GroundRulesWrote 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/chama-x/groundrules/hig-foundations)<a href="https://agentmods.dev/skills/chama-x/groundrules/hig-foundations"><img src="https://agentmods.dev/badge/skills/chama-x/groundrules/hig-foundations/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/chama-x/groundrules/hig-foundations"><img src="https://agentmods.dev/badge/skills/chama-x/groundrules/hig-foundations.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00182 | $0.01479 |
| Opus 5.5 | $0.00073 | $0.00592 |
| Sonnet 5.5 | $0.00036 | $0.00296 |
| Haiku 4.5 | $0.00018 | $0.00148 |
Grade A, and why
hig-foundations 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.
This is a copy
100% identical to hig-foundations — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 99 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Apple HIG: Design Foundations
Check for .claude/apple-design-context.md before asking questions. Use existing context and only ask for information not already covered.
Key Principles
-
Prioritize content over chrome. Reduce visual clutter. Use system-provided materials and subtle separators rather than heavy borders and backgrounds.
-
Build in accessibility from the start. Design for VoiceOver, Dynamic Type, Reduce Motion, Increase Contrast, and Switch Control from day one. Every interactive element needs an accessible label.
-
Use system colors and materials. System colors adapt to light/dark mode, increased contrast, and vibrancy. Prefer semantic colors (
label,secondaryLabel,systemBackground) over hard-coded values. -
Use platform fonts and icons. SF Pro, SF Compact, SF Mono by default. New York for serif. Follow the type hierarchy at recommended sizes. Use SF Symbols for iconography.
-
Match platform conventions. Align look and behavior with system standards. Provide direct, responsive manipulation and clear feedback for every action.
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Respect privacy. Request permissions only when needed, explain why clearly, provide value before asking for data. Design for minimal data collection.
-
Support internationalization. Accommodate text expansion, right-to-left scripts, and varying date/number formats. Use Auto Layout for dynamic content sizing.
-
Use motion purposefully. Animation should communicate meaning and spatial relationships. Honor Reduce Motion by providing crossfade alternatives.
Reference Index
| Reference | Topic | Key content |
|---|---|---|
| accessibility.md | Accessibility | VoiceOver, Dynamic Type, color contrast, motor accessibility, Switch Control, audio descriptions |
| app-icons.md | App Icons | Icon grid, platform-specific sizes, single focal point, no transparency |
| branding.md | Branding | Integrating brand identity within Apple's design language, subtle branding, custom tints |
| color.md | Color | System colors, Dynamic Colors, semantic colors, custom palettes, contrast ratios |
| dark-mode.md | Dark Mode | Elevated surfaces, semantic colors, adapted palettes, vibrancy, testing in both modes |
| icons.md | Icons | Glyph icons, SF Symbols integration, custom icon design, icon weights, optical alignment |
| images.md | Images | Image resolution, @2x/@3x assets, vector assets, image accessibility |
| immersive-experiences.md | Immersive Experiences | AR/VR design, spatial immersion, comfort zones, progressive immersion levels |
| inclusion.md | Inclusion | Diverse representation, non-gendered language, cultural sensitivity, inclusive defaults |
| layout.md | Layout | Margins, spacing, alignment, safe areas, adaptive layouts, readable content guides |
| materials.md | Materials | Vibrancy, blur, translucency, system materials, material thickness |
| motion.md | Motion | Animation curves, transitions, continuity, Reduce Motion support, physics-based motion |
| privacy.md | Privacy | Permission requests, usage descriptions, privacy nutrition labels, minimal data collection |
| right-to-left.md | Right-to-Left | RTL layout mirroring, bidirectional text, icons that flip, exceptions |
| sf-symbols.md | SF Symbols | Symbol categories, rendering modes, variable color, custom symbols, weight matching |
| spatial-layout.md | Spatial Layout | visionOS window placement, depth, ergonomic zones, Z-axis design |
| typography.md | Typography | SF Pro, Dynamic Type sizes, text styles, custom fonts, font weight hierarchy, line spacing |
| writing.md | Writing | UI copy guidelines, tone, capitalization rules, error messages, button labels, conciseness |
What ships with it
18 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.
- references/accessibility.md 5.0 KB
- references/app-icons.md 2.5 KB
- references/branding.md 1.2 KB
- references/color.md 2.8 KB
- references/dark-mode.md 1.7 KB
- references/icons.md 2.4 KB
- references/images.md 2.3 KB
- references/immersive-experiences.md 5.2 KB
- references/inclusion.md 3.6 KB
- references/layout.md 3.9 KB
- references/materials.md 4.3 KB
- references/motion.md 1.8 KB
- references/privacy.md 3.3 KB
- references/right-to-left.md 2.2 KB
- references/sf-symbols.md 2.6 KB
- references/spatial-layout.md 1.6 KB
- references/typography.md 2.9 KB
- references/writing.md 1.4 KB
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 · 99 lines · 182 tokens per session scan A a1535ddde3c6
hig-foundations is a skill published in the GitHub repository chama-x/GroundRules (5 stars, last pushed 2mo ago), licensed MIT. It adds 182 tokens to every session and 1,479 once invoked, about $0.0007 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to hig-foundations, differing in 0 lines, and is treated as a copy.
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mobile-ui-ux
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Use when building or changing any interactive mobile UI - VoiceOver/TalkBack labels, grouping, headings, focus order, Dynamic Type/font scale, reduce motion, contrast, and the automated check for each stack.
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