SKILL.md
SwiftUI Design Skill
TL;DR: Design SwiftUI apps that look intentionally crafted, not AI-generated. Follow the 6 Anti-Slop Rules, use the Design Direction workflow when requirements are vague, and always pass the 5-Dimension Review before shipping.
When to Use
- Designing new SwiftUI views or screens from scratch
- Reviewing or improving existing UI quality
- Creating iOS app prototypes or mockups
- Choosing a visual style or design direction
- Integrating brand assets into SwiftUI
- When someone says "the UI looks generic" or "make it look better"
- When building a new feature that needs visual design
When NOT to Use
- Pure backend / API work with no UI
- Fixing SwiftUI compilation errors (use swiftui-expert-skill instead)
- Performance optimization of existing views (use swiftui-expert-skill)
- Accessibility compliance only (use swiftui-expert-skill's accessibility topic)
Prerequisites
- Xcode 16+ with iOS 18+ / macOS 15+ SDK
- SwiftUI framework (not UIKit unless explicitly requested)
- Familiarity with SwiftUI view hierarchy and modifiers
Core Design Philosophy
These 6 principles guide every design decision. They are distilled from real-world design practice and anti-patterns observed in AI-generated UI.
Principle 1: Start From Context, Never Blank
Before designing any screen, ask:
- Is there an existing design system, UI kit, or Figma file?
- Is there an existing codebase with established visual language?
- Are there brand guidelines or a style guide?
If no context exists, create a brand-spec.md first (see Brand Asset Protocol below).
Principle 2: Junior Designer Mode — Hypothesize Early, Iterate Fast
Don't wait for the "perfect" design. Show hypotheses with placeholders early:
- Gray boxes for images are better than bad AI-generated SVGs
- System fonts with good spacing > custom fonts with bad spacing
- A rough but honest layout > a polished but generic one
Principle 3: Offer Variations, Not Finals
Always present 2-3 distinct design directions, not one "final answer." Each variation should:
- Represent a different design philosophy (e.g., editorial, functional, expressive)
- Have a clear rationale for why it works
- Be visually distinct — not just color swaps
Principle 4: Placeholder > Bad Implementation
If you cannot source a real asset (icon, image, illustration):
- Use a clean gray placeholder with clear labeling
- Never use AI-generated SVG clipart
- Never use emoji as icon substitutes in production UI
- For icons, prefer SF Symbols (Apple's built-in icon library)
Principle 5: System First, Don't Fill
Every element must earn its place. Before adding any UI element, ask:
- Does this serve the user's goal?
- Can this be combined with something else?
- What happens if I remove it?
Whitespace is a feature, not emptiness.
Principle 6: Anti-AI-Slop
These patterns are banned in production UI. See references/anti-ai-slop.md for detailed rules.
Banned visual patterns:
- ❌ Purple-to-blue gradient backgrounds
- ❌ Emoji as functional icons
- ❌ Rounded cards with left-border accent color
- ❌ Generic "hero section" with centered text over gradient
- ❌ Inter/Roboto as display fonts on Apple platforms
- ❌ Neon-on-dark "cyber" aesthetic (#0D1117 base)
- ❌ Symmetric 3-column feature grids
- ❌ AI-drawn SVG illustrations or CSS silhouettes
What to do instead:
- ✅ Single warm accent color on neutral background
- ✅ SF Symbols for icons, or custom icon set
- ✅ Serif display font (e.g., New York, Georgia) for headings
- ✅ Restrained info density — let content breathe
- ✅ One signature detail at 120% effort per screen
- ✅ Real photography or clean placeholders
Brand Asset Protocol
When building UI for a specific brand, follow this 5-step hard flow:
- Ask — Request brand guidelines, logo files, color palette, typography
- Search — If not provided, search the web for "[brand name] brand guidelines"
- Download — Get actual asset files (PNG/SVG logos, font files)
- Verify — Confirm colors match official sources (check hex values)
- Write brand-spec.md — Document: primary/secondary colors, fonts, logo usage rules, spacing tokens
Quality threshold: 5 real brand colors, 10 verified design tokens, 2 font families, 8pt spacing grid.
If no brand exists, create a brand-spec.md with:
- 1 primary accent color (warm, not purple-blue gradient)
- 1 neutral palette (grays with warm undertone)
- 1 display font + 1 body font (SF Pro default is fine)
- 8pt spacing grid
Design Direction Workflow
When requirements are vague or the user asks "what style should we use?", follow this workflow:
Phase 1: Understand Context (5 min)
- Ask: What is the app? Who is the user? What platform (iOS/macOS/watchOS)?
- Ask: Any reference apps or websites they admire?
- Check: Existing design system or brand assets?
Phase 2: Recommend 3 Directions
Present 3 distinct design philosophies from different schools:
| School | Example Directions |
|---|---|
| Information | Clean data-first, chart-heavy, Bloomberg-style |
| Editorial | Magazine layout, serif typography, generous whitespace |
| Expressive | Bold color, asymmetric layout, motion-forward |
| Functional | Dense utility, monospace accents, minimal decoration |
| Warm Minimal | Soft neutrals, rounded shapes, subtle texture |
Phase 3: Present Visual Anchors
For each direction, describe:
- Color palette (3-5 colors with hex values)
- Typography pairing (display + body)
- Layout density (comfortable / compact / spacious)
- Signature detail (one standout element per screen)
Phase 4: Let User Choose
Present options clearly. After choice, lock in the design system.
SwiftUI Design Workflow
Step 1: Define the Design System (Before Coding)
Create or confirm these design tokens:
// Requires: references/swift-extensions.md (Color(hex:) extension)
// DesignTokens.swift
enum DesignTokens {
// Colors
static let accent = Color(hex: "E85D3A") // Warm coral
static let background = Color(hex: "FAFAF8") // Warm white
static let textPrimary = Color(hex: "1A1A1A") // Near-black
static let textSecondary = Color(hex: "6B6B6B") // Muted gray
// Typography
static let displayFont = "New York" // Serif for headings
static let bodyFont = "SF Pro" // System default
// Spacing (8pt grid)
static let spaceXS: CGFloat = 4
static let spaceS: CGFloat = 8
static let spaceM: CGFloat = 16
static let spaceL: CGFloat = 24
static let spaceXL: CGFloat = 32
static let spaceXXL: CGFloat = 48
// Corner radius
static let radiusS: CGFloat = 8
static let radiusM: CGFloat = 12
static let radiusL: CGFloat = 16
}
Step 2: Build the Layout Hierarchy
Follow the layout patterns in references/layout-patterns.md:
- Start with the primary content container
- Use
VStackfor vertical flow,HStackfor horizontal - Use
LazyVGrid/LazyHGridfor grid layouts - Use
ScrollViewwith.scrollTargetBehavior(.paging)for paged content - Avoid
GeometryReader— prefercontainerRelativeFrame(iOS 17+)
Step 3: Apply Typography Hierarchy
Follow references/typography-color.md:
- Display (screen titles): Serif font, 28-34pt, bold
- Heading (section titles): Sans-serif, 20-24pt, semibold
- Body (content text): Sans-serif, 15-17pt, regular
- Caption (labels, metadata): Sans-serif, 12-13pt, secondary color
Step 4: Add the Signature Detail
Each screen should have ONE element that goes 120% — a custom animation, a unique layout choice, a distinctive color moment. This is what makes the design memorable.
Examples:
- A custom pull-to-refresh with brand-colored animation
- A card that expands with a spring animation on tap
- A header that uses the brand's display font at an oversized scale
- A subtle parallax effect on scroll
Step 5: Review Against Checklist
Before shipping, run the 5-Dimension Review (see references/design-review.md).
Common Mistakes to Avoid
| Mistake | Fix |
|---|---|
Using UIColor or NSColor | Use Color (SwiftUI native) |
UIScreen.main.bounds for sizing | Use containerRelativeFrame or geometry-based modifiers |
| Default blue tint everywhere | Define a custom accent color in design tokens |
| No spacing system (random padding values) | Use 8pt grid: 4, 8, 16, 24, 32, 48 |
| Emoji as icons | Use SF Symbols or custom icon assets |
| Purple-blue gradient background | Use solid warm neutrals |
| All content in one giant VStack | Break into semantic sections with clear hierarchy |
| No visual hierarchy (everything same size) | Use 3+ type scales (display, heading, body, caption) |
| Ignoring dark mode | Define semantic colors that adapt to appearance |
| Generic "Welcome!" hero section | Show actual content immediately |
Quick Reference: Topic Router
| Topic | Reference File |
|---|---|
| Anti-AI-Slop Rules (detail) | references/anti-ai-slop.md |
| Layout Patterns & Grids | references/layout-patterns.md |
| Typography & Color Systems | references/typography-color.md |
| 5-Dimension Design Review | references/design-review.md |
| Swift Extensions (required) | references/swift-extensions.md |
| Brand Spec Template | templates/brand-spec.md |
Validation Checklist
Before considering any SwiftUI design complete, verify:
- Design tokens defined (colors, fonts, spacing)
- No banned AI-slop patterns present
- Typography has clear hierarchy (3+ scales)
- Spacing follows 8pt grid
- Dark mode colors defined and tested
- One signature detail per screen
- SF Symbols used for icons (not emoji)
- Minimum 44×44pt tap targets
- No
GeometryReaderorUIScreen.main.bounds - 5-Dimension Review score ≥ 7/10 on all dimensions
