Documented component states turn reuse into testable behavior

A reusable component needs documented states, content constraints, interaction behavior, accessibility expectations, and failure conditions.

Static screenshots omit focus, loading, validation, empty, disabled, responsive, and assistive technology behavior.

Storybook stories capture granular variations for development, documentation, visual checks, interaction tests, and automated accessibility testing.

Automation remains incomplete because real composition, content, browsers, and users expose additional barriers.

Semantic tokens across supported themes make component states visually systematic and easier to inspect.

Contribution review for shared components verifies whether documented states suit broader product contexts.

Each published component should include runnable examples, expected behavior, known limits, and an accountable owner.

Reuse becomes safer when documentation operates as executable evidence rather than a decorative catalog.