Interaction Patterns

Codifiable UI interaction patterns that prevent common UX failures. Covers loading states, content pagination, disclosure patterns, overlays, drag-and-drop, tab overflow, and notification systems — all with accessibility baked in.

Quick Reference

Rule	File	Impact	When to Use
Skeleton Loading	rules/interaction-skeleton-loading.md	HIGH	Content-shaped placeholders for async data
Infinite Scroll	rules/interaction-infinite-scroll.md	CRITICAL	Paginated content with a11y and keyboard support
Progressive Disclosure	rules/interaction-progressive-disclosure.md	HIGH	Revealing complexity based on user need
Modal / Drawer / Inline	rules/interaction-modal-drawer-inline.md	HIGH	Choosing overlay vs inline display patterns
Drag & Drop	rules/interaction-drag-drop.md	CRITICAL	Reorderable lists with keyboard alternatives
Tabs Overflow	rules/interaction-tabs-overflow.md	MEDIUM	Tab bars with 7+ items or dynamic tabs
Toast Notifications	rules/interaction-toast-notifications.md	HIGH	Success/error feedback and notification stacking
Cognitive Load Thresholds	rules/interaction-cognitive-load-thresholds.md	HIGH	Enforcing Miller's Law, Hick's Law, and Doherty Threshold with numeric limits
Form UX	rules/interaction-form-ux.md	HIGH	Target sizing, label placement, error prevention, and smart defaults
Persuasion Ethics	rules/interaction-persuasion-ethics.md	HIGH	Detecting dark patterns and applying ethical engagement principles

Total: 10 rules across 6 categories

Decision Table — Loading States

Scenario	Pattern	Why
List/card content loading	Skeleton	Matches content shape, reduces perceived latency
Form submission	Spinner	Indeterminate, short-lived action
File upload	Progress bar	Measurable operation with known total
Image loading	Blur placeholder	Prevents layout shift, progressive reveal
Route transition	Skeleton	Preserves layout while data loads
Background sync	None / subtle indicator	Non-blocking, low priority

Quick Start

Skeleton Loading

function CardSkeleton() {
  return (
    <div className="animate-pulse space-y-3">
      <div className="h-48 w-full rounded-lg bg-muted" />
      <div className="h-4 w-3/4 rounded bg-muted" />
      <div className="h-4 w-1/2 rounded bg-muted" />
    </div>
  )
}

function CardList({ items, isLoading }: { items: Item[]; isLoading: boolean }) {
  if (isLoading) {
    return (
      <div className="grid grid-cols-3 gap-4">
        {Array.from({ length: 6 }).map((_, i) => (
          <CardSkeleton key={i} />
        ))}
      </div>
    )
  }
  return (
    <div className="grid grid-cols-3 gap-4">
      {items.map((item) => <Card key={item.id} item={item} />)}
    </div>
  )
}

Infinite Scroll with Accessibility

function InfiniteList({ fetchNextPage, hasNextPage, items }: Props) {
  const sentinelRef = useRef<HTMLDivElement>(null)

  useEffect(() => {
    const observer = new IntersectionObserver(
      ([entry]) => { if (entry.isIntersecting && hasNextPage) fetchNextPage() },
      { rootMargin: "200px" }
    )
    if (sentinelRef.current) observer.observe(sentinelRef.current)
    return () => observer.disconnect()
  }, [fetchNextPage, hasNextPage])

  return (
    <div role="feed" aria-busy={isFetching}>
      {items.map((item) => (
        <article key={item.id} aria-posinset={item.index} aria-setsize={-1}>
          <ItemCard item={item} />
        </article>
      ))}
      <div ref={sentinelRef} />
      {hasNextPage && (
        <button onClick={() => fetchNextPage()}>Load more items</button>
      )}
      <div aria-live="polite" className="sr-only">
        {`Showing ${items.length} items`}
      </div>
    </div>
  )
}

Rule Details

Skeleton Loading

Content-shaped placeholders that match the final layout. Use skeleton for lists, cards, and text blocks.

Load: rules/interaction-skeleton-loading.md

Infinite Scroll

Accessible infinite scroll with IntersectionObserver, screen reader announcements, and "Load more" fallback.

Load: rules/interaction-infinite-scroll.md

Progressive Disclosure

Reveal complexity progressively: tooltip, accordion, wizard, contextual panel.

Load: rules/interaction-progressive-disclosure.md

Modal / Drawer / Inline

Choose the right overlay pattern: modal for confirmations, drawer for detail views, inline for simple toggles.

Load: rules/interaction-modal-drawer-inline.md

Drag & Drop

Drag-and-drop with mandatory keyboard alternatives using @dnd-kit/core.

Load: rules/interaction-drag-drop.md

Tabs Overflow

Scrollable tab bars with overflow menus for dynamic or numerous tabs.

Load: rules/interaction-tabs-overflow.md

Toast Notifications

Positioned, auto-dismissing notifications with ARIA roles and stacking.

Load: rules/interaction-toast-notifications.md

Cognitive Load Thresholds

Miller's Law (max 7 items per group), Hick's Law (max 1 primary CTA), and Doherty Threshold (400ms feedback) with specific, countable limits.

Load: rules/interaction-cognitive-load-thresholds.md

Form UX

Fitts's Law touch targets (44px mobile), top-aligned labels, Poka-Yoke error prevention with blur-only validation, and smart defaults.

Load: rules/interaction-form-ux.md

Persuasion Ethics

13 dark pattern red flags to detect and reject, the Hook Model ethical test (aware, reversible, user-benefits), and EU DSA Art. 25 compliance.

Load: rules/interaction-persuasion-ethics.md

Key Principles

1. Keyboard parity — Every mouse interaction MUST have a keyboard equivalent. No drag-only, no hover-only.
2. Skeleton over spinner — Use content-shaped placeholders for data loading; reserve spinners for indeterminate actions.
3. Native HTML first — Prefer <dialog>, <details>, role="feed" over custom implementations.
4. Progressive enhancement — Features should work without JS where possible, then enhance with interaction.
5. Announce state changes — Use aria-live regions to announce dynamic content changes to screen readers.
6. Respect scroll position — Back navigation must restore scroll position; infinite scroll must not lose user's place.

Anti-Patterns (FORBIDDEN)

• Spinner for content loading — Spinners give no spatial hint. Use skeletons matching the content shape.
• Infinite scroll without Load More — Screen readers and keyboard users cannot reach footer content. Always provide a button fallback.
• Modal for browsable content — Modals trap focus and block interaction. Use drawers or inline expansion for browsing.
• Drag-only reorder — Excludes keyboard and assistive tech users. Always provide arrow key + Enter alternatives.
• Toast without ARIA role — Toasts are invisible to screen readers. Use role="status" for success, role="alert" for errors.
• Auto-dismiss error toasts — Users need time to read errors. Never auto-dismiss error notifications.

Detailed Documentation

Resource	Description
references/loading-states-decision-tree.md	Decision tree for skeleton vs spinner vs progress bar
references/interaction-pattern-catalog.md	Catalog of 15+ interaction patterns with when-to-use guidance
references/keyboard-interaction-matrix.md	Keyboard shortcuts matrix for all interactive patterns (WAI-ARIA APG)

Related Skills

• ork:ui-components — shadcn/ui component patterns and CVA variants
• ork:animation-motion-design — Motion library and View Transitions API
• ork:accessibility — WCAG compliance, ARIA patterns, screen reader support
• ork:responsive-patterns — Responsive layout and container query patterns
• ork:performance — Core Web Vitals and runtime performance optimization