Apple Design (Apple Human Interface Guidelines reference skill)

This skill distills Apple's official design resources (developer.apple.com/design/) into ready-to-use reference material, so you can give interface design and review advice for iOS / iPadOS / macOS / watchOS / visionOS / tvOS apps that is grounded in current official guidance.

Grounded, or guessing

Every specific claim you make — a point value, a contrast ratio, a component's official name, an API name — is either grounded or it's a guess:

• Grounded — you read it in a references/ file in this skill, or you just fetched the official page.
• Guess — it came from training memory.

State guesses as guesses, never as specs. The HIG is retuned almost every year around WWDC, and June 2025 replaced the entire materials, icon, and control-appearance system with Liquid Glass — so training memory of "Apple design guidelines" likely predates that change, or mixes specs across platforms. When a claim can't be grounded, say so and hand the user the official URL.

Qualitative advice ("keep the primary action reachable one-handed") doesn't need this treatment. Numbers, official names, and specs do.

The overall structure of the HIG

The official HIG (developer.apple.com/design/human-interface-guidelines/) is organized into six top-level sections, from abstract to concrete: