TidyToolsAI Crawler Index · data as of · updated daily

AI crawler · Meta · User-triggered fetch

Which websites block meta-externalfetcher?

As of 2026-10-01, 74 of the 853 popular websites whose robots.txt we could read (8.7%) block meta-externalfetcher, Meta's user-triggered AI fetcher, on the home page; 11 more block it on some paths. Among the top 100 sites: 14.5%.

8.7%
of 853 readable sites block meta-externalfetcher
14.5%
of the top 100
#13
most blocked of 29 AI crawlers
768
sites allow it on the home page

Blocked by category

CategorySites readBlock meta-externalfetcher
News & media12627%
Social4818.8%
Other2607.7%
Travel137.7%
Reference437%
E-commerce585.2%
Entertainment684.4%
Tech1540.6%
AI90%
Education200%
Finance160%
Government330%
Telecom50%

Popular sites that block meta-externalfetcher (74)

Sites that block meta-externalfetcher on some paths (11)

Trend

The daily series for meta-externalfetcher starts on 2026-10-01; a trend appears here as days accumulate.

Latest changes

Block or allow meta-externalfetcher

User-agent: meta-externalfetcher
Disallow: /

Replace Disallow: / with Allow: / to let it in. A site that blocks training crawlers but wants to be cited in AI answers usually keeps the search and user-triggered crawlers allowed.

FAQ

How many websites block meta-externalfetcher?
As of 2026-10-01, 74 of the 853 popular websites whose robots.txt we could read (8.7%) block meta-externalfetcher, Meta's user-triggered AI fetcher, on the home page; 11 more block it on some paths. Among the top 100 sites: 14.5%.
What is meta-externalfetcher?
meta-externalfetcher is Meta's user-triggered AI fetcher: it fetches a page when a user asks the assistant about it. It is the #13 most blocked of the 29 AI crawlers in the index.
How do I block meta-externalfetcher in robots.txt?
Add these lines to https://<your-site>/robots.txt: "User-agent: meta-externalfetcher" followed by "Disallow: /". To allow it, use "Allow: /" instead. Well-behaved crawlers read robots.txt before fetching pages; firewall rules are needed to stop crawlers that ignore it.
How do I check whether my site blocks meta-externalfetcher?
Use the free AI crawler checker at tools.yukai.uk/free/ai-crawler-checker: it shows the status of meta-externalfetcher and 28 other AI crawlers with the exact robots.txt rule.

Other AI crawlers

Also from Meta: Meta-ExternalAgent (14.4%), meta-webindexer (6.3%), meta-externalads (3.8%).