You ran the Query Fan-Out Generator. You now have 30-60 sub-queries the AI engine probably decomposes your seed keyword into. Do you have a landing page for each? This scorer pulls titles, H1s, and meta from every URL in your sitemap and matches against each fan-out query. Coverage % = the fraction of queries with a matching page.
Large sitemaps will be sampled to 100 URLs to stay fast. Matching is token-overlap (Jaccard) on the query vs. page title+H1+meta. Score above 0.35 = match.