Key point. Meta-ExternalAgent is Meta's AI training crawler. It governs use of your content for model training. It follows robots.txt.
Meta-ExternalAgent at a glance
These are the facts our registry holds for Meta-ExternalAgent, checked against Meta's documentation on October 14, 2026.
| Vendor | Meta |
| Purpose | AI training |
| Type | User agent |
| Follows robots.txt | Yes; source: community ai.robots.txt list (commit 9ad8a47e) |
| Vendor documentation | Meta crawler page, checked October 14, 2026 |
| Published IP ranges | None listed in our registry |
What is Meta-ExternalAgent?
Meta-ExternalAgent is Meta's AI training crawler. It governs use of your content for model training.
In Meta's own words (Meta's crawler documentation, read October 14, 2026):
- “The Meta-ExternalAgent crawler crawls the web for use cases such as training foundation AI models or improving products by indexing content directly.”
Meta uses other names for other jobs: Meta-ExternalFetcher (AI user fetch). Each takes its own robots.txt group.
Does Meta-ExternalAgent follow robots.txt?
Yes, Meta-ExternalAgent follows robots.txt: our registry records this from the community ai.robots.txt list (commit 9ad8a47e).
A robots.txt rule records your request. It does not prove a crawler honours it, and firewall or CDN bot settings can refuse a crawler that robots.txt allows, so check those too.
How do I block Meta-ExternalAgent in robots.txt?
Add a group that names Meta-ExternalAgent and disallows the whole site:
User-agent: Meta-ExternalAgent
Disallow: /To keep it out of one folder only, disallow that path instead, for example Disallow: /private/.
How do I allow Meta-ExternalAgent?
Meta-ExternalAgent is allowed by default: if no group names it and no User-agent: * rule blocks it, it may read every page. A crawler obeys the most specific group that names it and falls back to User-agent: * only when no group names it (RFC 9309), so if a catch-all rule blocks crawlers, add a group for it:
User-agent: Meta-ExternalAgent
Allow: /How can I tell if a request really comes from Meta-ExternalAgent?
Treat the name alone as a claim. User agents can be faked, and our registry lists no published IP-range file for Meta-ExternalAgent, so there is no list to match the request's address against.
How often do startup websites block Meta-ExternalAgent?
Our AI Crawler Access Report read the robots.txt files of 600 sampled startup websites on October 7, 2026. This is its row for Meta-ExternalAgent, across the 569 sites whose answer it could read:
| Crawler | Type | Blocked on at least one path | Blocked on all six paths | Named in the file |
|---|---|---|---|---|
| Meta-ExternalAgent | AI training | 7 of 569 sites (1.2%; 95% interval 0.6% to 2.5%) | 4 of 569 sites (0.7%; 95% interval 0.3% to 1.8%) | 40 of 569 sites (7.0%; 95% interval 5.2% to 9.4%) |
“Blocked” means the file disallows the crawler on at least one of six common paths (/, /pricing, /blog/, /docs/, /about, /product).
The report's headline figure, for the three AI search crawlers it tracked: “3 of 569 startup websites (0.5%; 95% interval 0.2% to 1.5%) block at least one AI search crawler (Elementera AI Crawler Access Report, October 2026).”
The figures describe that sample of Y Combinator-backed software companies on the day we fetched it. The method, the intervals and the full table are in the AI Crawler Access Report.
How do I check whether my robots.txt blocks Meta-ExternalAgent?
Read the group by hand: our free crawler checker covers 13 crawlers, and Meta-ExternalAgent is not one of them yet.
- Open
yoursite.com/robots.txt. - Look for a
User-agent: Meta-ExternalAgentline. If there is one, only that group applies to Meta-ExternalAgent. - If there is none, the
User-agent: *group applies. - Within the group, the longest matching
AlloworDisallowrule for a path wins.
Where can I see every AI crawler?
Our list of AI crawlers shows all 26 names in our registry, filtered by purpose. The same data is a free JSON download in our AI crawler registry.
Frequently asked questions
Three questions site owners ask about this name, each answered in one paragraph.
Should I block Meta-ExternalAgent?
That is a choice about model training, not about search. Blocking Meta-ExternalAgent does not remove your pages from AI search engines, whose crawlers have their own names.
Does blocking Meta-ExternalAgent affect other crawlers?
No. robots.txt groups are matched by name, so a group for Meta-ExternalAgent applies only to Meta-ExternalAgent. Meta's other names (Meta-ExternalFetcher) need their own groups.
How do I see whether Meta-ExternalAgent visits my site?
Search your server or CDN logs for Meta-ExternalAgent in the user agent. User agents can be faked, and our registry lists no published IP-range file for it, so treat the name alone as a claim.
Work with us
There are two ways to work with us. Teams that want the work done for them can use our managed AEO services: Book a call. Teams that want to see where they stand first can start with Lenz, our free analysis of how ChatGPT and Gemini answer their buyers' questions: Get your free AI visibility report.
How this page was made
A script builds this page from our AI crawler registry, the vendor crawler pages we read on October 14, 2026, and, for the blocking figures, the AI Crawler Access Report. Every sentence in quotation marks was checked against the vendor's page that day. Soroush Mehri reviewed the page, and Mojtaba Ebadi approved it for publication.
Sources
- Meta, crawler documentation: developers.facebook.com (read October 14, 2026)
- ai.robots.txt, community list of AI agents: github.com/ai-robots-txt/ai.robots.txt
- Koster, Illyes, Zeller and Sassman, “Robots Exclusion Protocol”, RFC 9309, IETF, 2022: rfc-editor.org
- Elementera, AI Crawler Access Report, October 2026: /resources/ai-crawler-access-report