Claude-User: what it is and how to allow or block it

By the Variask team · Updated

In short

Claude-User is Anthropic's user triggered fetcher. Fetches a page when a Claude user asks a question that needs it. Allow it. Each visit is a real person asking Claude about your topic.

  • Operator: Anthropic
  • Type: User triggered fetcher
  • robots.txt token: Claude-User
  • Anthropic says Claude-User follows robots.txt.

robots.txt rules

Copy the group you need into the robots.txt file at the root of your site. Keep only one option per bot.

At a glance

DetailClaude-User
OperatorAnthropic
TypeUser triggered fetcher
What it doesFetches a page when a Claude user asks a question that needs it.
robots.txt tokenClaude-User
Example user agentContains "Claude-User"
Follows robots.txtAnthropic says Claude-User follows robots.txt.
How to verifyMatch the user agent and check its behaviour in your logs.
If you block itClaude cannot read your page when a user asks about it.
SourceAnthropic help center article on crawlers and robots.txt

User agent version numbers change over time. Match on the token, not the full string.

What Claude-User does

Claude-User visits a page on behalf of a person using Claude, for example when they ask about a topic that needs current web content or share a link. Anthropic says disabling it may reduce your visibility for user directed web search.

Should you allow or block it?

Allow it. Each visit is a real person asking Claude about your topic.

If you block it: Claude cannot read your page when a user asks about it.

  • Training crawlers decide whether your content helps build future models. Blocking them does not remove you from AI search today.
  • Search crawlers decide whether AI engines can find and cite your pages. Blocking them usually costs visibility.
  • User triggered fetchers read a page because a person asked. Blocking them stops the AI reading you at the moment someone is interested.

How to find Claude-User in your logs

Search your server or CDN access logs for the token Claude-User. This command counts visits by IP, path and status code in a standard access log:

grep -i "Claude-User" access.log | awk '{print $1, $7, $9}' | sort | uniq -c | sort -rn | head

A run of 403 or 503 status codes means your firewall or bot protection is blocking it, even if robots.txt allows it. That is one of the most common hidden reasons sites lose AI visibility.

How to tell if a visit is genuine

Anyone can put Claude-User in a user agent string, so the name alone proves nothing. Match the user agent and check its behaviour in your logs.

Other Anthropic bots

  • Claude-SearchBot: ai search crawler. Crawls the web to improve the quality and relevance of Claude's search results.
  • ClaudeBot: training crawler. Collects public web content that may be used to train Anthropic's Claude models.

Questions

Common questions

Claude-User is Anthropic's user triggered fetcher. Fetches a page when a Claude user asks a question that needs it.

Anthropic says Claude-User follows robots.txt.

Add a robots.txt group with User-agent: Claude-User and Disallow: /. For a hard block, also deny it in your firewall or CDN.

Claude cannot read your page when a user asks about it.

Not always. User agents can be faked. Match the user agent and check its behaviour in your logs.

Go further

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