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-platforms/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-platforms)<a href="https://agentmods.dev/skills/chama-x/groundrules/hig-platforms"><img src="https://agentmods.dev/badge/skills/chama-x/groundrules/hig-platforms/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-platforms"><img src="https://agentmods.dev/badge/skills/chama-x/groundrules/hig-platforms.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 | $0.00168 | $0.01180 |
| Opus 5.5 | $0.00067 | $0.00472 |
| Sonnet 5.5 | $0.00034 | $0.00236 |
| Haiku 4.5 | $0.00017 | $0.00118 |
Grade A, and why
hig-platforms 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-platforms — 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 — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Apple HIG: Platform Design
Check for .claude/apple-design-context.md before asking questions. Use existing context and only ask for information not already covered.
Key Principles
-
Each platform has a distinct identity. Do not port designs between platforms. Respect each platform's conventions, interaction models, and user expectations.
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iOS: touch-first. Direct manipulation on a handheld screen. Optimize for one-handed use. Navigation uses tab bars and push/pop stacks.
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iPadOS: expanded canvas. Support Split View, Slide Over, and Stage Manager. Use sidebars and multi-column layouts. Support pointer and keyboard alongside touch.
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macOS: pointer and keyboard. Dense information display is acceptable. Use menu bars, toolbars, and keyboard shortcuts extensively. Windows are resizable with precise control.
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tvOS: remote and focus. Viewed from a distance. Design for the Siri Remote with focus-based navigation. Large text, simple layouts, linear navigation.
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visionOS: spatial interaction. 3D environment using windows, volumes, and spaces. Eye tracking for targeting, indirect gestures for interaction. Respect ergonomic comfort zones.
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watchOS: glanceable and brief. Information consumable at a glance. Brief interactions. Digital Crown, haptics, and complications for timely content.
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Games: own paradigm. Free to define in-game interaction models, but still respect platform conventions for system interactions (notifications, accessibility, controllers).
Reference Index
| Reference | Topic | Key content |
|---|---|---|
| designing-for-ios.md | iOS | Touch, tab bars, navigation stacks, gestures, screen sizes, safe areas |
| designing-for-ipados.md | iPadOS | Multitasking, sidebars, pointer, keyboard, Apple Pencil, Stage Manager |
| designing-for-macos.md | macOS | Menu bars, toolbars, window management, keyboard shortcuts, dense layouts, Dock |
| designing-for-tvos.md | tvOS | Focus engine, Siri Remote, lean-back experience, content-forward, parallax |
| designing-for-visionos.md | visionOS | Spatial computing, windows/volumes/spaces, eye tracking, hand gestures, depth |
| designing-for-watchos.md | watchOS | Glanceable UI, Digital Crown, complications, notifications, haptics |
| designing-for-games.md | Games | Controllers, immersive experiences, platform-specific conventions, accessibility |
What ships with it
7 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 · 85 lines · 168 tokens per session scan A a2681ef51856
hig-platforms is a skill published in the GitHub repository chama-x/GroundRules (5 stars, last pushed 2mo ago), licensed MIT. It adds 168 tokens to every session and 1,180 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-platforms, differing in 0 lines, and is treated as a copy.
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