Meta title & description length
Open Graph & Twitter Card tags
Heading hierarchy (H1→H6)
robots.txt & sitemap validation
SSL certificate inspection
Core Web Vitals (FCP, LCP, CLS)
Gzip / Brotli compression
Render-blocking resources
Mobile viewport & responsiveness
LLM crawler access (GPTBot, ClaudeBot…)
Answer format score for AI citation
Content chunkability for AI extraction