On-page SEO audit for any live URL. Returns a 0-100 SEO score plus the raw signals behind it: title tag and meta description with their lengths, canonical URL, robots directives, the full H1-H3 heading map, image alt-text coverage, Open Graph and Twitter card completeness, and whether schema.org structured data is present. Fetches the live page on every call, so results reflect the page as it is now. Use it to audit a landing page, diagnose weak search rankings, or inspect a competitor.