The prompt

Build an HTTP cache-policy simulator with Tailwind CSS. Include controls for public or private caching, max-age, stale-while-revalidate, and immutable behavior. Show the generated Cache-Control header, a request-age slider, response outcome badge, browser and CDN decision steps, and a horizontal freshness timeline. Add JavaScript that recalculates HIT, STALE, REVALIDATE, or MISS behavior from the policy, updates the header, and explains each decision in plain language.

Paste it into Claude, Cursor, v0 or any AI coding tool. Prefer the finished markup? Open the Tailwind source.