Why this matters
Most sites can be reached at several addresses: with or without "www", with or without a trailing slash, sometimes with tracking codes added. Without a canonical tag, AI sees four or five copies of the site and doesn't know which one to trust — so it may trust none of them. The canonical tag points at one official address and says "this is the real page."
Check the platform first
Wix, Squarespace, and Shopify add canonical tags automatically — if the report flagged this, something unusual is going on (a custom template, an app, or a misconfiguration). WordPress sites using Yoast SEO or Rank Math also get canonicals automatically.
Hand this to the client's web person
This one is a quick job for whoever built or maintains the site. Send them this message:
"Hi — we had the website checked for how well AI assistants can read it, and it found that the pages are missing the canonical link tag (<link rel="canonical">).
Could you add it to the page template? It should go inside the <head> section of every page, pointing at that page's main URL (the version with the preferred domain — with or without www, whichever the site uses everywhere).
We'll re-run the scan after to confirm it's fixed. Thanks!"
After the fix
Ask the web person to confirm when it's live, then run a new SERAVERRA scan. The metadata check reads the pages fresh each time.