React: making UI states explicit in the agentic era

When an agent changes a UI, checking a single account cannot cover every role, plan, or feature flag. Matt Rothenberg shows how values scattered across hooks, providers, and layouts can hide overlooked states — such as a Delete button shown to a view-only user.

Making display state an explicit component input lets teams render relevant combinations directly, test them, or compare them in a visual grid. Storybook and Playwright complement this approach, but they do not choose which scenarios to cover; that decision still matters.