meta-externalagent: what it is, who runs it, and how to allow or block it

meta-externalagent is a crawler run by Meta. It reads pages ahead of time, to train a model or to build an index. Its name in robots.txt, how it shows up in server logs, whether its identity can be checked, and how to allow or refuse it on each platform.

This response

You are ClaudeBot (Anthropic). Citable recognised you as an AI agent, so this is https://getcitable.in/crawlers/meta-externalagent with the UI removed — the content only. A browser asking for the same address gets the full designed page.

What meta-externalagent is

meta-externalagent is a crawler run by Meta. It reads pages ahead of time, to train a model or to build an index.

Should you refuse it?

meta-externalagent reads ahead of time. Refusing it keeps your pages out of what Meta collects them for. It does not change how Google or Bing rank you: search crawlers go by other names, with rules of their own.

robots.txt is a request. A crawler that honours it stays out; nothing in the file stops one that does not. What is enforced is what the server or the edge in front of it refuses.

Is a request really meta-externalagent?

Meta publishes no address list, so its crawlers are confirmed by reverse DNS instead: the connecting address must reverse to a name under .fbsv.net, and that name must resolve back to the same address.

Allowing or refusing meta-externalagent in robots.txt

Add one group for each name it answers to (meta-externalagent, FacebookBot). “Allow: /” lets it read the site and “Disallow: /” refuses it.

A group that names a crawler replaces the * group for that crawler; it does not add to it. Paths the * group closes are open to a crawler with its own group unless they are repeated there.

Refuse meta-externalagent:

User-agent: meta-externalagent
Disallow: /

User-agent: FacebookBot
Disallow: /

Allow meta-externalagent:

User-agent: meta-externalagent
Allow: /

User-agent: FacebookBot
Allow: /

Where the rule for meta-externalagent goes, platform by platform

Also run by Meta

Questions

What is meta-externalagent?

meta-externalagent is a crawler run by Meta. It reads pages ahead of time, to train a model or to build an index.

Who runs meta-externalagent?

Meta. It also reads websites as meta-externalfetcher, meta-webindexer; each has its own name in robots.txt and can be allowed or refused separately.

How do I allow or block meta-externalagent in robots.txt?

Add one group for each name it answers to (meta-externalagent, FacebookBot). “Allow: /” lets it read the site and “Disallow: /” refuses it. A group that names a crawler replaces the * group for that crawler; it does not add to it. Paths the * group closes are open to a crawler with its own group unless they are repeated there.

Should I block meta-externalagent?

meta-externalagent reads ahead of time. Refusing it keeps your pages out of what Meta collects them for. It does not change how Google or Bing rank you: search crawlers go by other names, with rules of their own.

How do I see meta-externalagent in my server logs?

In an access log meta-externalagent appears as a user agent containing “meta-externalagent” or “FacebookBot”.

How do I know a request is really meta-externalagent?

Meta publishes no address list, so its crawlers are confirmed by reverse DNS instead: the connecting address must reverse to a name under .fbsv.net, and that name must resolve back to the same address.

About Citable

Citable strips the UI from a website for AI agents and serves them only the content.

When an AI agent — ChatGPT, Claude, Perplexity or any of the 81 that Citable recognises — opens a page, Citable removes the theme, scripts, navigation and layout and serves only the content: the same facts, at the same URL, on the site's own domain. People and Google still get the full designed page.

How it works: https://getcitable.in/how-it-works · Summary for AI agents: https://getcitable.in/llms.txt


Source: https://getcitable.in/crawlers/meta-externalagent · Citable · Run the free audit · llms.txt · getcitable@gmail.com