Playbook: Fix your sitemap so lastmod actually earns recrawls

Playbook: Fix your sitemap so lastmod actually earns recrawls
Google now trusts lastmod again but only if it's honest. Here's the cleanup.

Setup:
— Audit current sitemap: does lastmod change on every build (bad) or only on real content edits (good)?
— Set lastmod to the actual content modification timestamp, in W3C/ISO 8601 format with timezone
— Drop changefreq and priority entirely Google ignores them
— Keep one URL per canonical, no noindexed or redirected URLs in the file
— Resubmit in GSC, watch the Sitemaps report 'Last read' date

What it does well: a clean lastmod gives Google a reliable recrawl signal and speeds up update detection.

Where it falls short: if you've cried wolf with build-time timestamps, Google may already distrust your lastmod and ignore it for weeks.

Pros:
— Free, big recrawl impact
— Simple to validate
Cons:
— Trust takes time to rebuild
— Easy to auto-break in CI

Best for: frequently-updated content sites. NOT for static brochure sites where pages rarely change.