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
| Detail | Claude-User |
|---|---|
| Operator | Anthropic |
| Type | User triggered fetcher |
| What it does | Fetches a page when a Claude user asks a question that needs it. |
| robots.txt token | Claude-User |
| Example user agent | Contains "Claude-User" |
| Follows robots.txt | Anthropic says Claude-User follows robots.txt. |
| How to verify | Match the user agent and check its behaviour in your logs. |
| If you block it | Claude cannot read your page when a user asks about it. |
| Source | Anthropic 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.