Meta-ExternalAgent user agent
Operated by Meta
Meta-ExternalAgent is Meta's crawler for use cases such as training AI models and improving products by indexing content directly.
The Meta-ExternalAgent bot at a glance
- Meta-ExternalAgent is operated by Meta and collects public web pages that may be used to train AI models.
- The robots.txt token for Meta-ExternalAgent is meta-externalagent.
- Blocking an AI training crawler has no effect on Google or Bing rankings.
- Meta-ExternalAgent robots.txt support: Yes.
- Recommendation for Generative Engine Optimization (GEO): Your choice.
What is Meta-ExternalAgent?
Meta-ExternalAgent collects public web pages for Meta, including for training foundation AI models such as Llama.
It is separate from FacebookExternalHit, so blocking it does not break link previews on Facebook, Instagram or WhatsApp.
Should you block Meta-ExternalAgent?
Blocking Meta-ExternalAgent is a business decision: it protects your content but can lower how well AI products know your brand.
| Effect on search rankings | Blocking an AI training crawler has no effect on Google or Bing rankings. |
|---|---|
| Effect on AI visibility | Blocking keeps your future pages out of that company's training data, so its models may know less about your brand over time. It does not remove you from that company's AI search, which uses a separate bot. |
| Follows robots.txt | Yes |
| Recommendation | Your choice |
How to block or allow Meta-ExternalAgent
Put the robots.txt rule in the file at the root of every domain and subdomain, for example https://example.com/robots.txt. The token meta-externalagent is matched case-insensitively.
robots.txt: block
# Block Meta-ExternalAgent
User-agent: meta-externalagent
Disallow: /robots.txt: allow
# Allow Meta-ExternalAgent
User-agent: meta-externalagent
Allow: /robots.txt: partial
# Keep Meta-ExternalAgent out of private areas only
User-agent: meta-externalagent
Disallow: /wp-admin/
Disallow: /cart/
Disallow: /checkout/
Disallow: /my-account/
Allow: /Nginx
# Nginx: return 403 to Meta-ExternalAgent
if ($http_user_agent ~* "(meta\-externalagent)") {
return 403;
}Apache
# Apache .htaccess: return 403 to Meta-ExternalAgent
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} (meta\-externalagent) [NC]
RewriteRule .* - [F,L]Cloudflare WAF
# Cloudflare > Security > WAF > Custom rule, action: Block
(http.user_agent contains "meta-externalagent")How to verify real Meta-ExternalAgent traffic
Meta publishes no IP list or reverse DNS pattern for Meta-ExternalAgent, so the user agent cannot be verified. Anyone can send the same string. Rate-limit unusual volume instead of trusting the name.
How to find Meta-ExternalAgent in your server logs
Search the web server access log for the token. The command below counts Meta-ExternalAgent requests per URL on Nginx or Apache.
grep -i "meta-externalagent" access.log | awk '{print $7}' | sort | uniq -c | sort -rn | head -20For a full report per AI bot, upload the log to the AI Log File Analyzer, a free tool by Justin Hà.
Meta-ExternalAgent user agent string
The full user agent Meta publishes for Meta-ExternalAgent. Version numbers such as Chrome/W.X.Y.Z change over time, so match the token, not the whole string.
meta-externalagent/1.1Meta-ExternalAgent FAQ
Meta-ExternalAgent identifies itself with the robots.txt token "meta-externalagent". A typical request header reads: meta-externalagent/1.1
Yes. Meta states that Meta-ExternalAgent follows robots.txt rules written for the "meta-externalagent" token.
Blocking an AI training crawler has no effect on Google or Bing rankings. Blocking keeps your future pages out of that company's training data, so its models may know less about your brand over time. It does not remove you from that company's AI search, which uses a separate bot.
Add two lines to the robots.txt file at the root of each domain and subdomain: "User-agent: meta-externalagent" followed by "Disallow: /". The token is case-insensitive. Changes can take up to 24 hours to be picked up.
Not reliably. Meta publishes no IP list or reverse DNS pattern for Meta-ExternalAgent, so anyone can send the same user agent. Rate-limit unusual volume instead of trusting the name.
Search your server access log for "meta-externalagent", for example with: grep -i "meta-externalagent" access.log. The AI Log File Analyzer by Justin Hà counts visits per AI bot from an uploaded log file.
Sources: Meta crawler documentation. Last reviewed by Justin Hà.
See which of these bots actually reach your website
The AI Log File Analyzer by Justin Hà counts visits from GPTBot, ClaudeBot, PerplexityBot and other AI crawlers in your server log, for free. The GEO Technical Package sets up robots.txt, llms.txt and crawler access for AI search.
