Knocklog

Meta-ExternalFetcher

Meta's assistant acting for a person.

Operator
Meta
Type
Assistant acting for a person
In the user agent
meta-externalfetcher
robots.txt token
meta-externalfetcher
Follows robots.txt
says it does not follow robots.txt
Official documentation
developers.facebook.com
Checked on
2026-11-04

What is Meta-ExternalFetcher?

Meta-ExternalFetcher is Meta's assistant acting for a person. It fetches a page because someone asked an AI assistant a question right now. Each visit is a person waiting for an answer that may mention you.

The operator's description: Fetches individual links at a user's request, including for agentic AI tasks. (developers.facebook.com)

How do I block or allow Meta-ExternalFetcher?

With robots.txt, using the token meta-externalfetcher. Meta says it does not follow robots.txt. To block the whole site:

User-agent: meta-externalfetcher
Disallow: /

To allow it, use Allow instead of Disallow. Before blocking, weigh what it brings: every visit is a person asking an assistant for something; blocking takes you out of those answers.

How do I see whether Meta-ExternalFetcher visits my site?

In your server or CDN access logs, look for meta-externalfetcher in the user agent. Google Analytics does not show these visits: agents do not run its JavaScript.

Anyone can copy the name in a user agent, so counting log lines is not enough. Knocklog reads your site's traffic on any host, confirms who is who, and shows how often Meta-ExternalFetcher came, which pages it read and what that brought you.

How do I know it is really Meta-ExternalFetcher?

Meta does not publish a way to verify Meta-ExternalFetcher. Any program can use that name, so Knocklog shows these visits as “unverified”, never as genuine.

Does Meta-ExternalFetcher visit your site?

See in seconds how your site treats AI agents. Then connect your traffic to learn who really came.

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