Anthropic

AI assistants

Claude-User

Fetches a page when a person asks Claude something that needs it.

Follows robots.txt
User agent token
Claude-User
Operator
Anthropic
Verification
Published IP list
Source
Anthropic documentation

What an AI assistant fetcher does

An assistant fetcher visits only when someone asks an AI assistant a question that needs your page. Each visit stands for a real person, often one who is about to click through, so blocking it usually costs you readers.

Unlike most assistant fetchers, Anthropic says this one honors robots.txt.

Block or allow Claude-User in robots.txt

Add one of these to the robots.txt file at the root of your domain. Crawlers read it before they fetch anything else.

Block Claude-User

User-agent: Claude-User
Disallow: /

Allow Claude-User

User-agent: Claude-User
Allow: /

More from Anthropic

ClaudeBotCollects public web content that Anthropic may use to train and improve Claude. Claude-SearchBotCrawls pages to improve the search results Claude cites.
Browse all 66 crawlersAI and search bots from 16 companies, with the rules to block or allow each one.

Questions, answered.

Claude-User is an AI assistant fetcher run by Anthropic. Fetches a page when a person asks Claude something that needs it.

Yes. Anthropic says Claude-User follows robots.txt. Unlike most assistant fetchers, Anthropic says this one honors robots.txt.

Add "User-agent: Claude-User" and "Disallow: /" to your robots.txt.

Check the request's IP address against the list Anthropic publishes. A user agent alone proves nothing, since any script can copy it.

Indirectly. Claude-User opens your page because a person asked about it, and the answer can link back to you.

Usually not. Each visit stands for a person asking about your page, so blocking Claude-User turns readers away.

In its own documentation at https://support.claude.com/en/articles/8896518-does-anthropic-crawl-data-from-the-web-and-how-can-site-owners-block-the-crawler. Every fact on this page comes from there.

Still have questions? We're happy to help.

Read the docs Contact support

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