seo-rendering (M4)

Content that only exists after hydration is invisible to any consumer that does not run JavaScript. Google renders JS (documented); most third-party AI crawlers are reported not to (directional — see Honesty), so a CSR-only shell is primarily an AI-visibility and crawl-efficiency problem. JS dependency also delays first paint; see references/cwv-thresholds.md for how this feeds LCP/INP.

Inputs

Work from the PageSnapshot named in your dispatch envelope: read parsed from <run_dir>/pages/<slug>.json and parsed_rendered, plus the render{needed,signals,used,confidence,hint,delta} block — the script already computed the raw-vs-rendered delta; raw_html_path/rendered_html_path name the files on disk; Grep pages/<slug>.html for verbatim evidence; site artifacts live in <run_dir>/site/{robots.json,sitemaps.json,discovery.json}. Deterministic findings already emitted by audit.mjs are listed in <run_dir>/findings.deterministic.json — do not re-emit those ids; add model-judged findings only. If invoked directly with a URL/path and no snapshot exists, first run node "${CLAUDE_PLUGIN_ROOT}/scripts/snapshot.mjs" <target> --out "${CLAUDE_PLUGIN_DATA}/runs" and use the printed snapshot path.

Audits

Working from the PageSnapshot (parsed_rendered when render.used is not none, else parsed) and the script-computed render.delta:

Content delta: diff raw_html_path vs rendered_html_path — measure the share of primary text, internal links, headings (h1–h3), and <script type="application/ld+json"> blocks that appear only after JavaScript runs.
Classify the strategy: CSR-only (empty/near-empty raw shell, content injected client-side) / SSR / SSG (prerendered static) / ISR (prerendered + revalidated). Use raw-HTML completeness and framework signals (__NEXT_DATA__, hydration markers, data-reactroot, build manifests).
Hydration-blocked text: primary content present in raw HTML but hidden/empty until hydration, or rendered only into a client-only island.
Lazy-loaded main content: above-the-fold or primary content that requires scroll/intersection/interaction to load — invisible to a non-interacting crawler.
AI gate: if the h1, primary body, or JSON-LD exist only in rendered_html_path, flag the page as not reliably consumable by non-JS AI crawlers.