# meta-externalagent > meta-externalagent is Meta's crawler for collecting training data. Meta's training corpus crawler. Meta is gathering training data. Cloudflare reports it as one of the busiest crawlers on the web. **Category:** AI crawlers **Also known as:** Meta meta-externalagent **Updated:** 2026-09-09 **Source:** https://truestat.io/glossary/meta-externalagent --- ## What meta-externalagent is This is the crawler that shows up in bandwidth bills. Cloudflare has reported it as the second most active crawler on the web after Googlebot, and unlike Googlebot it brings no search traffic back — it collects training material for Meta's models. For many sites it is the single largest volume decision on this page. Meta's crawlers are among the highest-volume on the web — Cloudflare has reported meta-externalagent second only to Googlebot in request count. Meta publishes no address list, so none of its traffic can be verified, and its share of a site's bandwidth is often the surprise on this page. On this site meta-externalagent is counted as training, which is the row it appears in on your dashboard. The category matters because it decides which number moves when this crawler visits, and the four are reported separately for exactly that reason. ## What its traffic looks like High volume, and this is the crawler most likely to be the largest single line in your bandwidth. Cloudflare has reported it second only to Googlebot across the web. It sweeps broadly rather than revisiting, so the traffic arrives as sustained crawling rather than as spikes. ## How it is verified Meta publishes neither a machine-readable list of the addresses this crawler uses nor a reverse DNS record pointing back at itself. The user-agent header is therefore the only evidence, and anyone can send it — so a visit is recorded as an unverified claim rather than as a confirmed fetch. That is not a gap in the measurement so much as an honest ceiling. A report that showed these as verified would be inventing a confidence nobody can support, and the number it produced would be the first thing to fall apart when somebody asked where it came from. ## If you block it Meta stops collecting your pages for model training. Because this is one of the highest-volume crawlers on the web, blocking it is also the single largest bandwidth saving available on this page. Nothing you see today changes if you block this. Training crawls feed models that ship months later, so the decision is about whether your work becomes part of a commercial model, not about this quarter's traffic. The honest counter-argument is that being in the training data is part of how a model comes to mention you at all. There is no measurement that settles this either way — anyone who tells you there is has not looked — so it is a decision about your terms rather than about your numbers. ## How it differs from Meta's other crawlers Meta sends 4 crawlers and gives each its own token, so they can be allowed and refused separately. The tokens differ by a few characters and what the fetch means does not: meta-externalfetcher — ai assistant. Fetches a specific URL a person asked Meta AI about. meta-webindexer — search indexing. Builds the index behind Meta AI search. meta-externalads — other bots. Meta's crawler for advertising and business products. Confusing two of these is the most common mistake with this operator, and it is expensive in one direction: a rule meant for the training crawler that lands on the search crawler removes you from results without stopping any training. ## One real request ```text meta-externalagent/1.1 (+https://developers.facebook.com/docs/sharing/webmasters/crawler) ``` ## Questions ### Is meta-externalagent in my logs really Meta? There is no way to prove it. Meta publishes neither an address list nor a reverse DNS record for this crawler, so the user agent is the only evidence and anyone can send it. We record the visit as an unverified claim rather than presenting it as confirmed. ### How do I tell meta-externalagent apart from Meta's other crawlers? By the token, and only by the token. Meta also sends meta-externalfetcher, meta-webindexer, meta-externalads, and the strings differ by a few characters while the jobs differ completely — one may be answering somebody's question while another collects training material. Match on the exact token rather than on the operator's name appearing anywhere in the header, or the four end up counted as one. ### Does meta-externalagent run JavaScript? No. It requests the HTML and leaves. That is why a browser-based analytics tag never records these visits: the tag is JavaScript, and nothing runs it. Seeing this crawler at all requires reading it server-side. ### Why is meta-externalagent counted as Training and not something else? Because that is the job this particular crawler does. Meta runs more than one — meta-externalfetcher, meta-webindexer, meta-externalads — and they are counted separately because the decisions about them are separate. Filing them together under one operator name would let ordinary indexing look like AI interest, which is the single most misleading thing an AI traffic report can do. ### Why does meta-externalagent not show up in Google Analytics? Google Analytics runs in the browser. This crawler never opens a browser — it requests the HTML, reads it, and leaves, so the tracking script is never executed and no event is ever sent. Every browser-based analytics tool has the same blind spot, which is why crawler traffic has to be read from the server side to be seen at all. ### Why can a meta-externalagent visit not be verified? Meta publishes neither a machine-readable list of the addresses its crawler uses nor a reverse DNS record pointing back at itself. With neither, the user-agent header is the only evidence, and anyone can send it. Rather than showing a confidence we cannot support, the visit is recorded as an unverified claim — which is also the honest answer to give anyone asking how much of your AI traffic is real. ## Related - https://truestat.io/glossary/meta-externalfetcher - https://truestat.io/glossary/meta-webindexer - https://truestat.io/glossary/meta-externalads - https://truestat.io/glossary/fcrdns - https://truestat.io/glossary/spoofed-crawler --- From the TrueStat glossary — https://truestat.io/glossary. Privacy-first web analytics that also shows you which AI assistants are reading your site.