Safe Official docs AI & LLM Bots

Claude-User

Q: What is the official user-agent string for Claude-User?

The official user-agent string for Claude-User is: Claude-User . This is the exact string you must use in robots.txt, Nginx, Apache, or Cloudflare firewall rules to target this bot. User-agent matching in robots.txt is case-insensitive, but the string must be spelled correctly. You can verify that a request genuinely comes from Claude-User by performing a reverse-DNS lookup on the source IP - legitimate bots resolve back to their operator's domain.

Q: Is Claude-User safe?

Yes. Claude-User is a documented bot: Anthropic publishes a page that names it and explains what it does.

Q: How do I block Claude-User in robots.txt?

Add the following lines to your /robots.txt file: User-agent: Claude-User Disallow: / This instructs Claude-User not to crawl any path on your site. The Disallow: / directive covers the entire domain including subfolders. To only block specific sections, replace / with the path (e.g., Disallow: /blog/ ). Note: robots.txt is publicly readable - any bot or human can inspect it at yourdomain.com/robots.txt .

Q: How do I verify if Claude-User is crawling my site?

Search your web server access logs for the string Claude-User (case-insensitive grep: grep -i "Claude-User" /var/log/nginx/access.log ). You can also check Google Search Console → Coverage → Crawl Stats for Googlebot variants. For Claude-User specifically, filter by user-agent in your log analysis tool (GoAccess, AWStats, etc.).

Operated by Anthropic

Scout's quick take

Claude-User visits a page only when a person asks Anthropic's assistant to open it. It is not a background crawler.

# Block only if you really mean to
User-agent: Claude-User
Disallow: /

Test my site for AI crawlers Build a full robots.txt

Quick Facts

User-Agent:: Claude-User
Category:: AI & LLM Bots
Operator:: Anthropic
Safety:: Safe
Blocking Impact:: Low - No SEO ranking impact
SEO Impact Score:: 2/10
Official docs:: support.claude.com

Confirmed by the operator

Anthropic names Claude-User on its own documentation page, linked above. The token, purpose and robots.txt behaviour on this profile come from that page, re-checked on October 19, 2026.

What is Claude-User?

Claude-User fetches pages when a person asks Claude a question that needs the web.

Anthropic lists Claude-User as user-directed retrieval; training is ClaudeBot. It identifies itself with the token Claude-User. Anthropic documents it at support.claude.com.

What happens if you block Claude-User?

Anthropic says disabling it "prevents our system from retrieving your content in response to a user query". No effect on Google or Bing.

Generally safe to allow; provides legitimate crawling value.

Want to see whether Claude-User actually visits you? Read how do I monitor AI bot traffic to my website?

How to block Claude-User with robots.txt

<code>User-agent: Claude-User</code> - Matching is case-insensitive. Robots.txt is fetched from the root of each subdomain separately.

Block completely (robots.txt)

User-agent: Claude-User
Disallow: /

Allow all (robots.txt)

User-agent: Claude-User
Allow: /

Block private only (robots.txt)

User-agent: Claude-User
Disallow: /private/
Disallow: /api/
Disallow: /admin/
Allow: /

Nginx server block

# Nginx: Hard-block Claude-User
if ($http_user_agent ~* "Claude\-User") {
    return 403 "Bot blocked";
}

Apache .htaccess

# Apache: Hard-block Claude-User
SetEnvIfNoCase User-Agent "Claude\-User" bad_bot
Order Allow,Deny
Allow from all
Deny from env=bad_bot

Meta robots tag

X-Robots-Tag header

X-Robots-Tag: noindex, nofollow

Is Claude-User safe to allow?

Yes. Claude-User is a documented bot: Anthropic publishes a page that names it and explains what it does.

Verify by reverse-DNS lookup: legitimate Claude-User requests resolve to anthropic's domain.

What does Claude-User do?

From Anthropic's own documentation.

Claude-User fetches pages when a person asks Claude a question that needs the web.
Not used to train AI models, according to the operator
Anthropic says disabling it "prevents our system from retrieving your content in response to a user query". No effect on Google or Bing.

Claude-User in context

Claude-User is a user-triggered agent operated by Anthropic. In plain terms, it fetches a page when a person asks an assistant or app to open it. Our database files it under AI and LLM crawlers and ranks it Tier 1, the small set whose absence you would notice in AI answers or search results. 14 of the 104 AI and LLM crawlers in our database share this tier.

Its safety rating is safe and its blocking impact is low. So the decision about Claude-User rests on what you want from Anthropic, not on its behaviour. How we rate safety and impact.

How site owners treat Claude-User

In our own study of robots.txt files across the Tranco top 10,000 sites (fetched October 20, 2026, 5,583 valid files), 357 files (6.4%) name Claude-User in a User-agent line, and 430 (7.7%) block it from the homepage. 214 of those blocks come from a group written for this crawler by name, and 216 come from a broad User-agent: * rule that catches it by accident. Larger sites are stricter: 14% of the top 1,000 block it, against 8.2% of the middle band and 6.3% of the tail.

Does it follow robots.txt?

Claude-User's operator says it follows robots.txt, so a correctly written Claude-User group is enough to control it.

Anthropic crawlers and close alternatives

Claude-User is one of 6 Anthropic crawlers in our database. A User-agent: Claude-User group controls Claude-User only; the other Anthropic tokens below need their own lines.

Claude-User: this crawler (Tier 1)
anthropic-ai: Anthropic AI (Deprecated), collects pages to train AI models (Tier 2)
Claude-Code: Claude Code Agent, fetches a page when a person asks an assistant or app to open it (Tier 2)
Claude-SearchBot: Claude Search, fetches a page when a person asks an assistant or app to open it (Tier 1)
Claude-Web: Claude Web (Deprecated), fetches a page when a person asks an assistant or app to open it (Tier 2)
ClaudeBot: Claude AI Training, collects pages to train AI models (Tier 1)

To give Claude-User the same answer as its siblings, stack User-agent: Claude-User with their lines above one set of rules; to treat Claude-User differently, give it its own group.

Other AI and LLM crawlers that do the same job (fetches a page when a person asks an assistant or app to open it) include ChatGPT Agent from OpenAI, ChatGPT Operator from OpenAI, ChatGPT-User from OpenAI, ChatGPT-User/2.0 from OpenAI, GrokAgent from xAI, muse- from Meta. Deciding about Claude-User is usually a decision about the whole group, so check how your file treats these too.

We first recorded Claude-User on March 17, 2026. Anthropic documents it on support.claude.com, and we recheck that page before each release.

Which rule Claude-User actually follows

Claude-User reads exactly one group in robots.txt, the most specific one that names Claude-User, and never combines rules across groups. This short file shows the trap:

User-agent: *
Disallow: /private/

User-agent: Claude-User
Disallow: /drafts/

Find the group. Claude-User looks for a group naming Claude-User. One exists, so it ignores User-agent: * completely.
Apply only that group. It is refused /drafts/ and nothing else.
The surprise. /private/ is open to Claude-User, because that rule lives in the * group it no longer reads. To keep it out of both, repeat Disallow: /private/ inside its own group.

Test yourself: does a rule under User-agent: * apply to Claude-User if the file also has a User-agent: Claude-User group?

No. Once a group names it, Claude-User reads only that group. Put every rule you want it to follow inside its own group.

Test yourself: will blocking Claude-User remove your pages from AI answers?

Often, yes. Claude-User is a user-triggered agent, so pages it cannot fetch can drop out of the answers or results it supports.

Test yourself: is User-agent: claude-user the same as User-agent: Claude-User?

Yes. RFC 9309 makes user-agent matching case-insensitive. Paths are a different story: Disallow: /Blog/ does not block /blog/.

Should you allow Claude-User? Decide by situation

Recommended setting for Claude-User by type of site
If you are...	Recommended setting
You publish content and want AI answers to cite it	Allow it. Claude-User fetches pages for answers, so blocking it can remove you from them.
You license content and want to stop AI training	Blocking it does not stop training, because Claude-User is a user-triggered agent. Block the operator's training crawler instead.
You run an online shop	Allow it on product and category pages, which are the pages shoppers ask assistants about.
Your server is under load from bots	Rate-limit before blocking. It is rated safe in our database.

Check Claude-User on your own site

Open /robots.txt on your domain and search for Claude-User. If it is not named, it follows User-agent: *.
List the Disallow lines in the group Claude-User follows and test your key URLs against them; the longest match wins, and Allow wins a tie.
Look beyond the file. A firewall or bot manager can refuse Claude-User even when robots.txt allows it, and that never shows in the file.
Run our AI crawlability test to see how Claude-User and every other crawler we track are treated in one pass, including firewall refusals.

Common mistakes with Claude-User

The errors we see most often with Claude-User in the files and firewalls we test:

Assuming a robots.txt rule will stop Claude-User. User-triggered fetches act for a person, and some operators say robots.txt may not apply to them. Check the operator's statement above.
Blocking Claude-User as if it were a bulk crawler. It fetches one page because a person asked; blocking it means that person's assistant cannot read your page.
Counting Claude-User visits as crawl volume. Each request maps to a real user question, which makes the paths it requests a useful signal of what people ask about you.

All three hide inside a file that looks correct, so check Claude-User from outside after every change.

Spotting Claude-User in your logs

robots.txt says what Claude-User may do; your access logs show what it actually did.

Count requests

On a server with standard Nginx or Apache logs, this counts matching requests per day (adjust the log path for your host):

grep -iE "Claude-User" /var/log/nginx/access.log \
  | awk '{print $4}' | cut -d: -f1 | sort | uniq -c

And this shows which paths it requested most, which is the quickest way to see whether your Disallow lines are being respected:

grep -iE "Claude-User" /var/log/nginx/access.log \
  | awk '{print $7}' | sort | uniq -c | sort -rn | head -20

Check the requests are genuine

Anyone can send the Claude-User user-agent, so confirm the source before acting on a match:

Claude-User: compare each address with the ranges at claude.com/crawling/bots.json. A request claiming to be Claude-User from outside them is not genuine.

Frequently Asked Questions

What is the official user-agent string for Claude-User?

The official user-agent string for Claude-User is: Claude-User. This is the exact string you must use in robots.txt, Nginx, Apache, or Cloudflare firewall rules to target this bot. User-agent matching in robots.txt is case-insensitive, but the string must be spelled correctly. You can verify that a request genuinely comes from Claude-User by performing a reverse-DNS lookup on the source IP - legitimate bots resolve back to their operator's domain.

Is Claude-User safe?

Yes. Claude-User is a documented bot: Anthropic publishes a page that names it and explains what it does.

Will blocking Claude-User hurt my SEO?

Anthropic says disabling it "prevents our system from retrieving your content in response to a user query". No effect on Google or Bing.

How do I block Claude-User in robots.txt?

Add the following lines to your /robots.txt file:

User-agent: Claude-User
Disallow: /

This instructs Claude-User not to crawl any path on your site. The Disallow: / directive covers the entire domain including subfolders. To only block specific sections, replace / with the path (e.g., Disallow: /blog/). Note: robots.txt is publicly readable - any bot or human can inspect it at yourdomain.com/robots.txt.

Does Claude-User respect robots.txt?

Yes. Anthropic says Claude-User "allows site owners to control which sites can be accessed through these user-initiated requests" via robots.txt.

How do I verify if Claude-User is crawling my site?

Search your web server access logs for the string Claude-User (case-insensitive grep: grep -i "Claude-User" /var/log/nginx/access.log). You can also check Google Search Console → Coverage → Crawl Stats for Googlebot variants. For Claude-User specifically, filter by user-agent in your log analysis tool (GoAccess, AWStats, etc.).

What is the crawl frequency of Claude-User?

Claude-User crawls at a moderate rate. If you notice excessive traffic in your logs, you can add a Crawl-delay directive:

User-agent: Claude-User
Crawl-delay: 10

(10 second delay between requests).

Can I block Claude-User from specific pages only?

Yes. Instead of a global Disallow: / you can restrict Claude-User to specific paths:

User-agent: Claude-User
Disallow: /private/
Disallow: /staging/
Allow: /

This allows Claude-User everywhere except the listed paths. Path matching in robots.txt uses prefix matching - Disallow: /private/ blocks /private/page.html but NOT /public/private/.

Does blocking Claude-User prevent AI training on my content?

Claude-User is not used for AI training, according to Anthropic. Anthropic lists Claude-User as user-directed retrieval; training is ClaudeBot.

Is there an alternative to robots.txt to opt out of Claude-User?

The opt-out Anthropic documents is robots.txt. A firewall, CDN or server rule that returns 403 for Claude-User enforces it. Per-bot meta tags and llms.txt are not opt-out mechanisms any major operator documents.