Meta-ExternalAgent: what it is and how to block it

Crawls the web for uses such as training foundation AI models or indexing content for Meta products.

Model trainingOperator: MetaMeta: Meta Web Crawlers

Does Meta-ExternalAgent follow robots.txt?

Meta shows a robots.txt example for meta-externalagent and says changes can take up to 24 hours because crawlers cache robots.txt.

What blocking it does

Opts your site out of this crawler, including its AI-training use.

Other Meta tokens

  • Meta-ExternalFetcher: user-requested fetch. Fetches individual links at a user’s request, including for agentic AI features.

Block Meta-ExternalAgent everywhere

User-agent: Meta-ExternalAgent
Disallow: /

Block only some folders

User-agent: Meta-ExternalAgent
Disallow: /members/
Disallow: /drafts/

Explicitly allow it

User-agent: Meta-ExternalAgent
Allow: /

A group that names Meta-ExternalAgent replaces the * group for it. Copy any shared rules into this group too. Test the result.

Meta-ExternalAgent questions

What is Meta-ExternalAgent?

Meta-ExternalAgent is operated by Meta. Crawls the web for uses such as training foundation AI models or indexing content for Meta products.

How do I block Meta-ExternalAgent?

Add "User-agent: Meta-ExternalAgent" followed by "Disallow: /" to your robots.txt. Meta shows a robots.txt example for meta-externalagent and says changes can take up to 24 hours because crawlers cache robots.txt.

What happens if I block Meta-ExternalAgent?

Opts your site out of this crawler, including its AI-training use.

Does blocking Meta-ExternalAgent block other Meta crawlers?

No. Meta documents Meta-ExternalFetcher separately; each needs its own User-agent line if you want to block it.