IncidentSeoIndexedPagesDropped

Severity: warning · Fires after: 6h · Rule: central/prometheus/rules/visibility.yml

What it means

An engine's indexed-page count for a site is more than 20% below a week ago. Pages are being removed from the index — this precedes, and causes, an impressions fall.

Expression

webmaster_indexed_pages
  < 0.8 * avg_over_time(webmaster_indexed_pages[1d] offset 7d)
and avg_over_time(webmaster_indexed_pages[1d] offset 7d) >= 20

For Google the count is verdict == "PASS" over the rotating URL-Inspection sweep, so it lags reality by up to one sweep cycle (~2.7 days for the wiki). Bing and Yandex report their own totals.

First checks

curl -sG 'http://192.168.0.5:9090/api/v1/query' \
  --data-urlencode 'query=sum by (state) (webmaster_url_coverage{site="<site>"})'

Where did the pages go? "Server error (5xx)" = Google's crawl failed; "Crawled – currently not indexed" = Google fetched them and declined (quality/duplication, or a rendering problem — see the Allow: /api/pages/ note in the wiki's robots.txt, where a blocked content API once made pages render empty); "Excluded by 'noindex'" or "Blocked by robots.txt" = a deploy changed directives.

Also confirm the number is trustworthy: URL-inspection sweep health on the search-visibility dashboard should show Sweep OK = 1 and a recent oldest result.

How to clear

Fix the cause, then request re-indexing in Search Console. The alert clears once the week-old baseline catches down to the new level.