web-vitals-and-seo

Put everything that must rank or be cited into the initial server HTML, and optimize the field data, not the lab score.

The failure this fixes

Two recurring failures. First: content, metadata, canonical, and JSON-LD are rendered after load via useEffect / client components — so the raw HTTP response is a blank shell. AI crawlers (GPTBot, ClaudeBot, PerplexityBot) run zero JavaScript, ever and see nothing; Googlebot's Wave-1 crawl also sees nothing and bets on a Wave-2 render queue that lags hours to weeks. Second: teams burn a sprint chasing Lighthouse 100 — a single simulated lab load on a throttled phone — while Google ranks on CrUX field data (real users, p75, 28 days). A page hits 95+ in the lab and still fails CWV in the field; the effort went to the wrong number.

When to use / when NOT to use