Design Handoff

Handoff is where design intent meets engineering reality. A poor handoff produces a poor implementation, regardless of how good the design was. This skill ensures every decision is documented clearly enough that an engineer who was not in the room can implement it faithfully.

When to Use

• Design critique is complete and issues are resolved
• Design work is ready for engineering implementation
• Engineering team needs specifications for components, layouts, or interactions

Process

Step 1: Assemble the Handoff Package

Gather all artefacts from the design process:

• Design brief (context and intent)
• Personas (who this serves)
• Design principles (what guides decisions)
• Visual specifications (layouts, colours, typography)
• Interaction specifications (states, transitions, feedback)
• Accessibility requirements (per component)
• Design system references (tokens, components used)

Step 2: Write Component Specifications

For each component or screen, provide:

## [Component/Screen Name]

### Purpose
[What this element does and why it exists]

### Visual Specification
- Layout: [positioning, spacing, alignment — reference tokens]
- Typography: [font, size, weight, line-height — reference tokens]
- Colour: [foreground, background, borders — reference tokens]
- Responsive behaviour: [how this adapts at each breakpoint]

### Interaction Specification
- States: [default, hover, focus, active, disabled, error, loading]
- Transitions: [what animates, duration, easing, reduced-motion alternative]
- Feedback: [what the user perceives at each state change]

### Accessibility Requirements
- Semantic element: [which HTML element to use]
- ARIA: [roles, labels, states — only if semantic HTML is insufficient]
- Keyboard: [tab order, interaction keys, focus management]
- Screen reader: [what is announced in each state]
- Contrast: [specific ratios for text and UI elements]
- Touch: [target sizes]
- Motion: [prefers-reduced-motion behaviour]

### Content
- Labels: [exact text for labels, buttons, headings]
- Error messages: [exact text for each error state]
- Help text: [exact text for instructions or hints]
- Alt text: [exact text for images]

### Design Rationale
[Why this component looks and behaves this way — reference design principles and persona needs]

Step 3: Document Decisions and Trade-offs

For decisions that might seem arbitrary or surprising to an engineer, explain:

• The decision: what was chosen
• The alternatives considered: what was not chosen
• The reason: why this option serves users better
• The accessibility driver: which inclusive design requirement influenced this

Step 4: Create an Accessibility Checklist

Provide a testing checklist specific to this design:

## Accessibility Testing Checklist

### Automated Testing
- [ ] Run axe-core or similar on all screens
- [ ] Verify colour contrast programmatically
- [ ] Validate HTML for correct semantics

### Keyboard Testing
- [ ] Tab through all interactive elements — order is logical
- [ ] Activate every interactive element via keyboard
- [ ] Verify no keyboard traps
- [ ] Verify focus is visible at all times

### Screen Reader Testing
- [ ] Navigate by headings — structure is clear
- [ ] Navigate by landmarks — regions are labelled
- [ ] Interact with forms — labels and errors are announced
- [ ] Verify live regions announce dynamic content

### Visual Testing
- [ ] Zoom to 200% — layout remains usable
- [ ] Enable high contrast mode — content is readable
- [ ] Enable dark mode — contrast ratios hold
- [ ] Simulate colour blindness — information is not lost

### Motion Testing
- [ ] Enable prefers-reduced-motion — animations are removed or reduced
- [ ] Verify no content flashes more than 3 times per second

Step 5: User Review

Present the handoff package to the user before sharing with engineering. Confirm:

• Is the rationale clear?
• Are there any design decisions that need more context?
• Are the accessibility requirements complete?

Save to: docs/designpowers/handoff/YYYY-MM-DD-<feature>-handoff.md

Integration

• Called by: designpowers-critique (after critique passes)
• Follows: All design skills
• Pairs with: verification-before-shipping (final check before declaring complete)