Building reusable AI components accelerates development and ensures consistent UX. Key components: 1) StreamingText: renders incrementally as tokens arrive. Uses useRef for cursor, CSS animation for blinking cursor effect. Accepts onComplete callback. 2) AISuggestionBox: shows AI suggestions with accept/reject/edit actions. Keyboard shortcuts (Tab to accept, Escape to dismiss). 3) AILoadingState: semantic skeleton with animated gradient, matches expected content layout. 4) ConfidenceIndicator: visual indicator (0-100%) with color coding (green >80, yellow 50-80, red <50). 5) ConversationMessage: renders user and AI messages with different styles, timestamps, copy button, feedback buttons. Component API design: follow shadcn/ui patterns with cn() for class merging, forward refs, aria labels, data-state attributes for CSS targeting. TypeScript: strict types for all props, generic types for data payloads. Storybook: document every component with multiple stories showing different states. Accessibility: ARIA live regions for streaming content (aria-live="polite"), keyboard navigation for all interactive elements, focus management after AI actions.