Anthropic-AI

What Anthropic-AI does

The anthropic-ai token spread through community blocklists in 2023 as the presumed name of Anthropic's training crawler. Anthropic's current documentation names three agents - ClaudeBot, Claude-User, and Claude-SearchBot - and does not mention anthropic-ai at all. Credible sightings of it in server logs are scarce; it may have been an early identifier, or simply a blocklist entry that outlived whatever briefly justified it. Nobody outside Anthropic knows, and Anthropic hasn't said.

Why it visits your site

It mostly doesn't. If you do see it in logs, verify carefully - undocumented tokens are easy for impostors to borrow.

The bigger picture: AI training crawlers

Training crawlers are the most economically lopsided visitors your server has. A search crawler takes your content and pays you back in ranked listings and click-throughs; a training crawler takes the same content to improve a commercial model and, by design, sends nothing in return. The visit itself is the entire transaction. That asymmetry is why training bots - not AI in general - are where most of the blocking debate actually lives, and why the publishing industry's response has split between refusal and negotiation: several large publishers block these crawlers outright, while others have signed licensing deals with the same operators. Both strategies start from the same place - knowing, concretely, how much of your archive is being read and by whom.

The norms here are young and still hardening. The better operators now publish user agents, IP ranges, and opt-out tokens, and honor robots.txt; others publish nothing and, by widely credited reports, crawl through disallow rules. Treat each crawler on its record rather than assuming the category behaves uniformly - and remember that a robots.txt line only ever governs the polite end of the spectrum.

Should you block it?

Keeping it in robots.txt costs nothing, and many blocklists include it for completeness. Just don't mistake it for actual control over Anthropic's crawling: that lives with the ClaudeBot token, plus Claude-User and Claude-SearchBot for fetching and search.

Block via robots.txt

Add these lines to the robots.txt at your site root to ask Anthropic-AI to stay away:

User-agent: anthropic-ai
Disallow: /

Remember that robots.txt is a request, not a lock - compliance is voluntary, and enforcement happens at the server. Viz's AI Control pairs robots.txt rules with server-level 403 responses and then probes your site to verify the block is actually holding.

How to see Anthropic-AI traffic on your site

You have three windows onto it, each with a catch. Raw hosting access logs contain every Anthropic-AI request, but many managed WordPress hosts don't expose them, and when they do you are grepping text files by hand. A CDN dashboard sees the traffic at the edge, but it lives outside WordPress and speaks in totals, not in your site's terms. And JavaScript analytics - GA4 and friends - will never show it at all, because Anthropic-AI doesn't run scripts.

Viz's answer is the request log: filter to Anthropic-AI and read exactly which URLs it fetched and when, right inside wp-admin - then watch the same filter after any blocking decision to see whether the visits stopped, slowed, or kept coming.