meta-externalagent
Crawls for training Meta's foundation AI models or improving its products by indexing content directly. Meta's documented way to block it is a robots.txt disallow.
Where this comes from
- Documented by the vendor. Source: developers.facebook.com
- Honours robots.txt.
- Counted in the readiness score. It can keep a site out of AI search or answers, so a block costs points.
In the top 1,000 websites
- 16.9% block it in robots.txt (96 of the 569 sites with a robots.txt), as of 2026-10-12.
- Method, limits and the full data: the October 2026 study of the top 1,000 websites.
What blocking it costs
Meta AI says this token controls more than training, so a block can keep your pages out of its answers or product features. The score counts it, so a block costs points.
The robots.txt lines
To let it in (a group that names the crawler replaces any wildcard rules for it, so this also lifts a User-agent: * block):
User-agent: meta-externalagent
Allow: /To keep it out:
User-agent: meta-externalagent
Disallow: /A rule in robots.txt is a request. Meta AI says this crawler honours it. The robots.txt generator writes a whole file with the same split: block the training crawlers, keep the search and answer crawlers.
Also from Meta AI
meta-externalfetcher· Fetches when a user asksFacebookBot· Training only
Does meta-externalagent get through on your site?
Run the free check: it reads your robots.txt against all 51 crawlers and tells you which ones can read you, and what to change.