`robots.noindex`

Default: error
Plugin: robots

A page does not ask search engines to leave it out of results.

Why: noindex, or none, removes the page from search results. It is often left over from a staging site.

The rule reads the robots and googlebot meta tags. For a URL, it also reads the X-Robots-Tag header, with its unscoped and googlebot: directives.

When off: pages with noindex pass. Turn the rule off for sites, or pages, that you do not want in search results.

<!-- ✗ Fails -->
<meta name="robots" content="noindex" />

<!-- ✓ Passes -->
<meta name="robots" content="index, follow" />

References

Google: Robots meta tag specifications: noindex and none leave the page out of results, from a meta tag or the X-Robots-Tag header.
Google: Block search indexing with noindex: How noindex works, and why the page must stay crawlable.