Meta-ExternalFetcher is a bot in the AI assistants and agents category, operated by Meta.
Crawler receives individual links at the user's initiative to support certain product features.
AI assistants fetch pages on demand when a user asks a chatbot or an agent to read, summarise or act on a URL. Each request is tied to a person, but the visit carries no ad impressions or analytics. Decide per agent whether the value is worth the load.
Meta-ExternalFetcher identifies itself with this user agent string:
meta-externalfetcher/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/crawler)Anyone can copy a user agent string. Transfon Security also checks where each request comes from, so a request that claims to be a known crawler but comes from the wrong network is treated as a fake, not as the real crawler.
We have not confirmed whether Meta-ExternalFetcher follows robots.txt. Add a rule, then check your logs to see that it stopped. robots.txt is a plain text file at the root of your domain, such as https://example.com/robots.txt.
User-agent: meta-externalfetcher Disallow: /
User-agent: meta-externalfetcher Disallow: /private/ Disallow: /search
User-agent: meta-externalfetcher Allow: /blog/ Disallow: /
User-agent: meta-externalfetcher Allow: / User-agent: * Disallow: /
User-agent: meta-externalfetcher group, Meta-ExternalFetcher ignores your User-agent: * rules, so repeat any that should still apply.meta-externalfetcher from Meta-ExternalFetcher's user agent; check Meta's own documentation if it publishes a different robots.txt name.Treat robots.txt as a statement of your policy, and enforce it where requests arrive.
Meta-ExternalFetcher reads pages for a person who asked an AI about them. The visit carries no ad impressions, so exclude it from ad requests and decide whether it may read paywalled content.
Transfon Security for publishersAgent visits can click through landing pages and fill in forms. Exclude Meta-ExternalFetcher from conversions so campaign optimisation is based on people.
Transfon Security for advertisersAgents like Meta-ExternalFetcher can compare prices and may soon place orders. Decide whether agents may reach checkout, and verify them before they do.
Transfon Security for e-commerceMeta-ExternalFetcher can sign up, log in and call endpoints on a user's behalf. Rate limit it on sign-up and API routes, where fake trials and abuse start.
Transfon Security for SaaS and APIsrobots.txt is a request, not an enforcement. Transfon Security shows Meta-ExternalFetcher by name in the Top Bots report, so you can see how often it visits and which pages it reads. Block or allow it with a User Agent rule, or slow it down with a rate limit decision rule.
Transfon Security
Meta-ExternalFetcher is a bot in the AI assistants and agents category, operated by Meta. Crawler receives individual links at the user's initiative to support certain product features.
We have not confirmed whether Meta-ExternalFetcher follows robots.txt. Add a robots.txt rule, then check your logs to see that it stopped, and block it by user agent if it did not.
Add "User-agent: meta-externalfetcher" followed by "Disallow: /" to the robots.txt file at the root of your site. To enforce it, block requests whose user agent contains "meta-externalfetcher/" at your WAF. In Transfon Security that is one User Agent block rule.
No. robots.txt is voluntary, so Meta-ExternalFetcher may not follow it, and anyone can send Meta-ExternalFetcher's user agent, so a fake Meta-ExternalFetcher ignores your rule. Enforce the rule where requests arrive, at your WAF, and check the source network.
AI assistants fetch pages on demand when a user asks a chatbot or an agent to read, summarise or act on a URL. Each request is tied to a person, but the visit carries no ad impressions or analytics. Decide per agent whether the value is worth the load.
Transfon Security identifies every bot in this directory in your traffic reports, flags fake search crawlers, and lets you allow, block or rate limit each bot.
Privacy, security, monetization, and performance insights. A few emails a month, no spam.