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site.sitemap-lastmod-missing

InfoSEO auditcrawl

A sitemap lists URLs but gives none of them a <lastmod>, so search engines cannot tell which pages changed. Bing calls lastmod a key signal for what to crawl again; Google uses it when it is consistently accurate.

What to change

Give each <url> a <lastmod> with the date its content last changed in substance (2026-11-09 or 2026-11-09T10:00:00+01:00), taken from the content, never the time the sitemap is built.

The documentation on blogs.bing.com

A finding of this rule on a page carries the exact edits for that page: the markup it quotes, and what to write instead.

When it runs

Runs on a crawl or a build directory. Info is a best practice: worth doing, rarely urgent, and --no-info leaves it out. Each finding takes 1 point off the page's score.

The severity here is the rule's usual one: a finding can be raised or lowered when the page gives a reason.

Run it, or skip it

Check a page for this rule alone, after a fix for instance:

npx @rivi-software/agentic-seo-check crawl https://example.com --rule site.sitemap-lastmod-missing

Or from an assistant, with the MCP tool seo_crawl_site:

{
  "url": "https://example.com",
  "rules": [
    "site.sitemap-lastmod-missing"
  ]
}

To leave it out of an audit, pass --disable site.sitemap-lastmod-missing on the command, or disableRules: ["site.sitemap-lastmod-missing"] to a tool.

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