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name: interface-design description: Design user interfaces. Use when creating layouts, wireframes, or UI specifications. Covers design principles and UI patterns. allowed-tools: Read, Write, Glob, Grep

Interface Design

Design Principles

1. Clarity

Make the interface obvious. Users shouldn't have to guess.

2. Consistency

Same actions, same results. Maintain patterns throughout.

3. Feedback

Respond to every action. Show progress, confirm success, explain errors.

4. Efficiency

Minimize steps. Optimize common workflows.

5. Forgiveness

Allow undo. Confirm destructive actions. Recover gracefully.

UI Patterns

Navigation

• Top Nav: Primary navigation, global actions
• Side Nav: Section navigation, hierarchical content
• Breadcrumbs: Show location in hierarchy
• Tabs: Switch between related views

Forms

• Label above input
• Clear validation messages
• Inline validation where helpful
• Logical field grouping
• Clear call-to-action

Feedback

• Loading states
• Success confirmations
• Error messages
• Empty states
• Progress indicators

Actions

• Primary action prominent
• Secondary actions subtle
• Destructive actions require confirmation
• Disabled states clear

Layout Principles

Visual Hierarchy

• Size indicates importance
• Color draws attention
• Spacing groups elements
• Alignment creates order

Grid System

Copy.container {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 1rem;
}

Responsive Design

• Mobile-first approach
• Breakpoints: 640px, 768px, 1024px, 1280px
• Fluid typography
• Flexible images

Design Specification

When handing off to development:

• Color values (hex/RGB)
• Typography (font, size, weight, line-height)
• Spacing (margins, padding)
• Component states (default, hover, active, disabled)
• Responsive behavior
• Animations/transitions