What is Meta-ExternalFetcher? AI crawler guide

Meta-ExternalFetcher is a crawler or fetcher associated with Meta. See source-graded user-agent, robots.txt, verification, and observation guidance.

What is Meta-ExternalFetcher?

Meta-ExternalFetcher is a documented Meta crawler or fetcher. Meta user-requested fetcher for AI and link features across Meta products.

Evidence status

Field Value
Evidence Officially documented
Lifecycle Active
Purpose interaction
robots.txt posture partial
Source checked 2026-06-11

Documented user-agent

meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/web-crawlers)

Meta-ExternalFetcher fires when a real user's question pulls in your page. To know how often Meta AI reaches for your brand at all, track your brand mentions in Meta AI.

robots.txt allow example

User-agent: Meta-ExternalFetcher Allow: /

robots.txt block example

User-agent: Meta-ExternalFetcher Disallow: /

What the rule can and cannot do

Robots.txt expresses an access policy to compliant automated crawlers. It does not authenticate the sender, remove content already collected, or guarantee that a model will use or not use content.

How to verify a request

Observed in Trakkr connected-site data

Measure Value
Matching signature Meta-ExternalFetcher
Classified requests 2781
Sites in sample 85
Window 2026-07-18 through 2026-08-17
Method Finalized daily crawler summaries from connected Trakkr sites, grouped by the crawler signature detected in each request.
Limits This is a connected-site sample, not a representative sample of the web. A matching user-agent or signature does not prove that the named operator sent the request. Counts describe classified request signatures, not market share or unique pages crawled.

JavaScript behavior

The cited operator material does not verify JavaScript rendering. Serve useful HTML before client-side JavaScript where possible.

Related bots

Frequently Asked Questions

What is Meta-ExternalFetcher?

Meta-ExternalFetcher is a officially documented crawler or fetcher record associated with Meta.

What user-agent does Meta-ExternalFetcher use?

meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/web-crawlers). Check the evidence status before attributing a matching request.

Can Meta-ExternalFetcher be blocked in robots.txt?

The record identifies Meta-ExternalFetcher as the token to review. Robots.txt is a request policy, not proof of model use or non-use.

How can I verify a Meta-ExternalFetcher request?

Treat the user-agent as a clue and look for operator-published IP, reverse-DNS, or signature guidance.

Data & Sources