Preview checks cannot prove how the public edge serves a page. Canonical verification belongs immediately after deployment while the release identity is still known.
Request the exact route
Use a client that does not follow redirects. The approved canonical route should return a successful response directly. Record any redirect as a failure to investigate, even when a browser eventually shows the expected content.
Compare all identity signals
Match the requested URL with the HTML canonical, Open Graph URL, structured-data URL, sitemap entry, and family index link. Normalize only documented conventions such as a single trailing-slash policy.
Check aliases separately
Known aliases may redirect, but they should not appear as competing sitemap entries or self-canonical pages. Document their destination and preserve intentional historical redirects.
Escalate before indexing signals spread
Correct a wrong canonical in the existing release rather than publishing duplicate content as a workaround. Save the direct response and extracted signals with the deployment record.
