Generate a Design Brief for Apple platform apps (iOS, iPadOS, macOS, watchOS) that serves as a long-lived, authoritative reference document for LLM-driven design decisions. Use when the user asks to "create a design brief", "define the design direction", "write a design brief for my app", or needs a stable reference that prevents design drift across multiple LLM sessions. The output is structured so another LLM can reliably parse and apply it. Assumes SwiftUI as the primary UI framework and Apple HIG as the baseline.
Generate opinionated, internally consistent Design Briefs for Apple platform apps. The brief captures design intent, encodes trade-offs, and provides decision heuristics — not feature lists. It acts as a stable reference document that future LLM sessions use to make aligned design decisions.
Every brief inherits these constraints from Apple's Human Interface Guidelines. Do not repeat them in the brief output — they are assumed. Only mention platform specifics when the product deviates from defaults or makes a deliberate choice between options.
Core principles: Clarity (content legible and focused), Deference (UI supports content, never competes), Depth (visual layers convey hierarchy).
Typography: San Francisco system font. Dynamic Type support required. Semantic styles: .largeTitle (34pt), .title (28pt), .headline (17pt semibold), .body (17pt), .caption (12pt). Minimum text: 11pt. Custom fonts must use relativeTo: for Dynamic Type scaling.
Colors: Semantic colors (Color(.label), Color(.systemBackground), etc.) adapt to light/dark mode automatically. System accent colors for interactive elements. Custom colors require both light and dark variants. WCAG AA contrast: 4.5:1 for text, 3:1 for large text and UI components.
Spacing: 8pt grid. Standard padding: 16pt. Touch targets: minimum 44x44pt.
Icons: SF Symbols (6000+). Use .symbolRenderingMode(.hierarchical) or .multicolor for semantic meaning. Custom icons only when SF Symbols lacks coverage.
Navigation patterns:
.presentationDetents([.medium, .large])Accessibility: VoiceOver labels on all interactive elements. Respect Reduce Motion, Increase Contrast, Bold Text. Never rely on color alone for meaning.
Platform differences:
Ask for the required field. Infer sensible defaults for optional fields and state assumptions explicitly. Actively encourage the user to share design inspiration — existing apps, screenshots, or references that capture the feel they're after. Inspiration produces significantly better briefs.
Required:
Optional (infer if not provided):
Do not repeat user input verbatim — fold it into the brief's structure.
Follow the exact output structure in references/output_template.md. Every section is mandatory.
Writing rules:
Before delivering, verify:
In subsequent sessions, the user (or another LLM) references the brief like this:
"Use the following Design Brief as the authoritative source for all design decisions. If a decision is not explicitly covered, infer the choice that best aligns with the Design Principles and Decision Heuristics."
This prevents the model from drifting or inventing a new aesthetic every turn. The brief is the source of truth.
references/output_template.md — The exact output structure to follow