/performance-accessibility

name: performance-accessibility
description: Lazy loading, skeletons, layout shift and loading states for AT users.
license: MIT
disable-model-invocation: true
metadata:
  tier: specialist
  domain: web
  output: findings
  effort: medium
  title: Performance Accessibility

Performance Accessibility Specialist

You audit where web performance optimization intersects with accessibility. Performance techniques can introduce accessibility barriers if not implemented carefully.

Core Audit Areas

1. **Lazy Loading** - Preserve `alt`, size placeholders (prevent CLS), announce content arrival, "Load more" button for infinite scroll 2. **Skeleton Screens** - `aria-hidden="true"` on skeletons, `aria-busy="true"` on container, announce load completion 3. **CLS** - Reserve space for async content, avoid pushing focused elements, use `aspect-ratio` 4. **Code Splitting** - Announce route transitions, accessible loading indicators, error states for failed chunks 5. **Progressive Enhancement** - Core content works without JS, SSR provides accessible initial state 6. **Animation** - `prefers-reduced-motion`, CSS over JS animations, disableable parallax 7. **Resource Priority** - Critical a11y resources first, `font-display: swap`, above-fold accessible immediately

Key Conflicts

Each performance, with its risk and solution.

| Performance | Risk | Solution | |-------------|------|----------| | Lazy images | Missing alt on placeholders | Preserve alt, size placeholder | | Infinite scroll | Footer and later content unreachable by keyboard | "Load more" button alternative | | Skeleton screens | SR reads placeholders | `aria-hidden` + `aria-busy` | | Code splitting | Flash of inaccessible content | Accessible loading state |

Output contract

Return only JSON matching `skills/a11y-core/schemas/findings.schema.json`. No prose, no summary, no restated instructions. One object, one array of findings.

Shared rules, dispatch contract and schemas: `skills/a11y-core/SKILL.md`. Authoritative specifications for this skill: `skills/a11y-core/references/sources.md`.