Why it matters
X shows a small summary card without it; title, description and image can fall back to Open Graph, but the card type can't.
How to fix it
Set twitter: { card: 'summary_large_image' } in the root layout metadata.
References
More seo rules
void seo reports 60 rules in this category. What search engines need from the raw response: status codes, titles and descriptions in <head>, self-referencing canonicals, one h1, crawlable links, Open Graph, icons, robots.txt and a sitemap with real dates.
og-incompleteog:description / og:site_name missing, or og:url ≠ canonicalog-image-invalidog:image isn't a reachable, absolute, raster image within size limitsog-image-sizeog:image is smaller than 1200×630 or far from 1.91:1og-image-metaog:image:width/height missing or wrong, or og:image:alt missingfaviconNo crawlable favicon in a Google-supported formatapple-touch-iconapple-touch-icon missing or not a 180×180 PNGmanifestWeb app manifest missing or incompletetheme-colorNo theme-color meta