Agent directory · AI assistant
Meta-ExternalFetcher
Fetches a page when someone using Meta AI, or another Meta product, asks for it, so it acts for a person in real time.
- Run by
- Meta
- Type
- AI assistant
- Robots.txt name
meta-externalfetcher- Verifiable
- No
What Meta-ExternalFetcher does
Fetches a page when someone using Meta AI, or another Meta product, asks for it, so it acts for a person in real time.
As an AI assistant, it fetches pages for a person, in real time, while they use an AI assistant. The kinds of AI agent that visit websites.
Should you allow it?
Almost always allow it. Blocking it means the assistant can't read your pages when a customer asks about you, so it answers from somewhere else. A decision guide for blocking or allowing AI crawlers.
How to allow or block Meta-ExternalFetcher
Meta-ExternalFetcher reads the meta-externalfetcher group in your robots.txt. To block it everywhere:
User-agent: meta-externalfetcher
Disallow: /To allow it everywhere, even if another rule blocks other bots:
User-agent: meta-externalfetcher
Allow: /Robots.txt is a request, not a lock: well-behaved crawlers follow it, impostors don't. Robots.txt for AI agents.
How it identifies itself
A typical user agent:
meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/crawler)How to tell if it's really Meta-ExternalFetcher
Meta doesn't publish IP ranges or a reverse DNS domain for Meta-ExternalFetcher, so a request can't be proven to come from it. Anyone can send its user agent, so treat the name alone as a claim, not proof. Ghost Agent Lab reports these requests as unverified rather than guessing.
Other agents from Meta
- Meta-ExternalAgent: AI training crawler
- facebookexternalhit: other bot
Every Meta agent, and a robots.txt for all of them →
Does Meta-ExternalFetcher visit your site? Ghost Agent Lab reads your CDN or server logs and shows every request from Meta-ExternalFetcher and 1,566+ other known agents: what they read, what your site sent back, and whether each request was genuine. See agent traffic, or check whether AI agents can use your site for free.