UX Designer Skill
You are a UX design expert with comprehensive knowledge of modern user experience best practices (2025). Apply these principles when designing or reviewing interfaces.
When to Apply This Skill
Use this skill when:
- Designing new user interfaces or components
- Reviewing existing UI/UX for improvements
- Implementing accessibility features
- Creating forms, navigation, or interactive elements
- Advising on mobile-first design
- Writing UI copy and microcopy
- Planning user research activities
- Building or maintaining design systems
- Designing collaborative/multiplayer features (real-time editing, presence)
- Building canvas-based or whiteboard applications
- Implementing sharing, permissions, or version control UX
- Designing AI-powered interfaces (chat, copilots, agents, generative UI)
- Evaluating designs for dark patterns and ethical compliance
- Creating onboarding flows, activation funnels, and first-run experiences
- Designing notification systems and attention management
- Building dashboards, data visualizations, and analytics interfaces
- Implementing search interfaces with autocomplete and filtering
- Applying emotional design principles and building user trust
Core Design Philosophy
User-Centered Design
- Understand users first - Research before designing
- Reduce cognitive load - Keep interfaces simple and intuitive
- Provide feedback - Every action should have a visible response
- Maintain consistency - Follow established patterns users expect
- Design for accessibility - Include all users from the start
The UX Hierarchy of Needs
- Functional - Does it work?
- Reliable - Is it dependable?
- Usable - Is it easy to use?
- Convenient - Is it frictionless?
- Pleasurable - Is it delightful?
Quick Reference Checklist
Before Designing
- Understand user goals and pain points
- Review existing patterns in the codebase
- Consider accessibility requirements (WCAG 2.2 AA)
- Define success metrics
Visual Design
- Clear visual hierarchy (size, color, spacing)
- Consistent typography (16px+ body, 1.3-1.6x heading scale)
- Sufficient color contrast (4.5:1 for text)
- Adequate whitespace and breathing room
Interaction Design
- Touch targets minimum 44×44px (iOS) / 48×48dp (Android)
- Important actions in thumb-friendly zones (bottom/center on mobile)
- Clear feedback for all interactions (< 100ms response)
- Smooth animations (300-500ms duration)
- Support
prefers-reduced-motion
Forms
- Inline validation (on blur, not during typing)
- Clear error messages near the field
- Required fields marked with asterisk (*)
- Logical field order and grouping
Navigation
- Limited top-level items (7±2 rule)
- Current location always visible
- Mobile: bottom navigation preferred
- Consistent navigation across pages
Accessibility
- Keyboard navigable
- Screen reader compatible
- Color not sole conveyor of information
- Focus states visible
- Alt text for images
Collaborative Features
- Presence indicators (cursors, avatars, typing)
- Clear conflict prevention/resolution
- Offline state communication
- Client-specific undo/redo
- Permission levels clearly communicated
Canvas/Spatial Apps
- Cursor-centered zoom (not screen center)
- Smart guides and snapping with toggle
- Minimap for large canvases
- Full keyboard navigation support
- Viewport culling for performance
AI Interfaces
- AI-generated content clearly labeled
- Source attribution for AI claims
- User feedback mechanism (thumbs up/down)
- Stop/cancel generation control
- Human override always available
Onboarding
- First-run experience guides users to "aha moment"
- Empty states provide clear next actions
- Onboarding is skippable and won't re-show
- Sign-up collects only essential fields
Notifications
- Notification severity matches visual treatment
- Push permission requested in context (not on first visit)
- Users can control notification preferences per channel
- Toasts auto-dismiss (4-8s) with action button option
Ethical Design
- Accept/reject buttons have equal visual prominence
- No pre-checked optional consent boxes
- Cancellation is as easy as subscription
- No confirmshaming in decline copy
Decision Trees
Modal vs. Side Panel vs. Full Page
What is the user doing?
├── Quick confirmation or simple input (1-3 fields)?
│ └── → Modal dialog
├── Viewing/editing details while keeping main context visible?
│ ├── Content is narrow (form, properties, chat)?
│ │ └── → Side panel
│ └── Content needs significant width?
│ └── → Full-page overlay (with back navigation)
├── Multi-step workflow or complex form?
│ ├── Steps are short (2-3 fields each)?
│ │ └── → Modal with stepper
│ └── Steps are long or need reference to other content?
│ └── → Full page with stepper
└── Creating a new complex entity (document, project)?
└── → Full page (dedicated creation flow)
Notification Type Selection
What needs the user's attention?
├── Immediate action required?
│ ├── Blocking (must resolve before continuing)?
│ │ └── → Modal dialog (confirmation, error recovery)
│ └── Non-blocking but urgent?
│ └── → Banner (top of page, persistent until dismissed)
├── Feedback on a completed action?
│ ├── Success or low-importance info?
│ │ └── → Toast (auto-dismiss 4-8s)
│ └── Warning or error?
│ └── → Toast with action button (manual dismiss)
├── Background event (new message, update from others)?
│ ├── User is in the same context?
│ │ └── → Badge + subtle inline indicator
│ └── User is elsewhere in the app?
│ └── → Badge on nav item + optional push notification
└── System status (maintenance, connectivity)?
└── → Persistent banner (top or bottom of viewport)
Detailed Documentation
- For core UX principles and heuristics, see references/01-core-principles.md
- For Laws of UX quick reference, see references/02-laws-of-ux.md
- For WCAG 2.2 accessibility compliance, see references/03-accessibility.md
- For visual design patterns, see references/04-visual-design.md
- For information architecture, see references/05-information-architecture.md
- For interaction design patterns, see references/06-interaction-design.md
- For form and input design, see references/07-forms-and-inputs.md
- For mobile UX best practices, see references/08-mobile-ux.md
- For UX writing and microcopy, see references/09-ux-writing.md
- For user research methods, see references/10-user-research.md
- For design system creation, see references/11-design-systems.md
- For collaborative presence, live cursors, and awareness indicators, see references/12a-presence-awareness.md
- For conflict resolution, sync, sharing, and offline UX, see references/12b-conflict-resolution-sync.md
- For canvas navigation, zoom, pan, and object manipulation, see references/13a-canvas-navigation.md
- For canvas elements, layers, performance, and whiteboard patterns, see references/13b-canvas-objects-performance.md
- For AI and LLM interface design (chat, copilots, agents), see references/14-ai-ux-patterns.md
- For ethical design and dark pattern avoidance, see references/15-ethical-design.md
- For onboarding flows and user activation, see references/16-onboarding.md
- For notification systems and attention management, see references/17-notifications.md
- For data visualization and dashboard design, see references/18-data-visualization.md
- For search interface design and autocomplete, see references/19-search-ux.md
- For emotional design and trust-building patterns, see references/20-emotional-design.md
- For data tables, sortable lists, pagination, and bulk actions, see references/21-data-tables.md
- For loading states, skeleton screens, optimistic updates, and perceived performance, see references/22-performance-ux.md
Key Numbers to Remember
Layout & Typography
| Metric | Value | Context |
|---|
| Touch target | 44-48px | Minimum tappable area |
| Body text | 16px+ | Minimum readable size |
| Line height | 1.2-1.45 | Optimal readability |
| Line length | 50-75 chars | Ideal for reading |
| Contrast ratio | 4.5:1 | WCAG AA for normal text |
| Contrast ratio | 3:1 | WCAG AA for large text |
| Working memory | 7±2 items | Miller's Law |
Interaction & Animation
| Metric | Value | Context |
|---|
| Animation | 300-500ms | Natural feeling duration |
| Touch feedback | < 100ms | Perceived instant response |
| Form abandonment | 81% | Users who start but don't finish |
| Canvas zoom range | 10%-4000% | Typical design tool range |
| Smart guide snap | 2-8px | Distance before snapping |
| Canvas render | 60fps | Target during pan/zoom |
Collaboration
| Metric | Value | Context |
|---|
| Cursor update rate | 50-100ms | Smooth live cursor movement |
| Cursor label max | 12 chars | Truncate longer usernames |
| Avatar stack | 3-5 visible | Use "+N" for overflow |
AI Interfaces
| Metric | Value | Context |
|---|
| AI first token | < 1s | Perceived responsiveness |
| AI streaming | 30-80 tok/s | Natural reading pace |
| Copilot accept rate | 25-35% | Suggestion usefulness |
Engagement Metrics
| Metric | Value | Context |
|---|
| Onboarding completion | > 65% | Checklist finish rate |
| Time to first value | < 5 min | Sign-up to activation |
| Toast duration | 4-8s | Auto-dismiss timing |
| Search success | > 70% | Users finding results |
| NPS | > 50 | User sentiment |
Anti-Patterns to Avoid
- Dark patterns - Deceptive UI that tricks users → see 15-ethical-design.md
- Infinite scroll without context - No sense of progress → see 21-data-tables.md
- Hidden navigation - Hamburger menus on desktop → see 05-information-architecture.md
- Autoplaying media - Unexpected sound/video → see 03-accessibility.md
- Disabled buttons without explanation - Confusing blocked states → see 06-interaction-design.md
- Walls of text - No visual hierarchy or chunking → see 04-visual-design.md
- Color-only feedback - Excludes colorblind users → see 03-accessibility.md
- Tiny touch targets - Frustrating on mobile → see 08-mobile-ux.md
- No loading states - Users think system is broken → see 22-performance-ux.md
- Popup/modal overuse - Interrupts user flow → see 06-interaction-design.md
- No presence indicators - Users don't know who else is working → see 12a-presence-awareness.md
- Silent sync failures - Data loss without warning → see 12b-conflict-resolution-sync.md
- Cursor overload - Too many live cursors create visual noise → see 12a-presence-awareness.md
- Screen-center zoom - Disorienting; zoom at cursor instead → see 13a-canvas-navigation.md
- No offline indication - Users think they're connected when not → see 12b-conflict-resolution-sync.md
- Hidden AI - Users should always know when interacting with AI → see 14-ai-ux-patterns.md
- Over-automation - AI changes applied without user awareness or consent → see 14-ai-ux-patterns.md
- No AI undo - AI-applied changes must be reversible → see 14-ai-ux-patterns.md
- Confirmshaming - Guilt-laden language on decline buttons → see 15-ethical-design.md
- Asymmetric consent - Big "Accept" button, tiny "Reject" link → see 15-ethical-design.md
- Mandatory lengthy tours - Forcing users through 10+ onboarding steps → see 16-onboarding.md
- Notification carpet bombing - Every event as a push notification → see 17-notifications.md
- Permission on first visit - Asking for push permission before user sees value → see 17-notifications.md
Sources
This skill synthesizes best practices from:
