Claude Code Agent: User Agent, robots.txt Rules & Safety

Q: What user-agent string does Claude Code Agent use?

Claude Code Agent is reported to identify itself with Claude-Code. That spelling comes from ai.robots.txt, not from Anthropic, which has not published crawler documentation naming it. Use it in robots.txt as the best available match, and treat a request carrying it as a clue rather than proof of who sent it.

Q: Is Claude Code Agent safe?

Claude Code Agent is rated Safe in this directory, meaning there are no credible public reports of abusive crawling under this name. It is a Reported token: Anthropic has not published documentation for it, so its purpose, crawl rate and robots.txt behaviour are not confirmed by the operator, and anyone can send the same user-agent string. Allow or block it on its stated purpose, and back the robots.txt rule with a firewall rule if the traffic matters to you.

Q: Will blocking Claude Code Agent hurt my SEO?

✅ No SEO Impact - Blocking Claude Code Agent does not affect your rankings in Google, Bing, or any other search engine. Claude Code Agent is an AI crawler, not a traditional search indexer. You can freely block it via User-agent / Disallow: / without any SEO penalty.

Q: How do I block Claude Code Agent in robots.txt?

Add the following lines to your /robots.txt file: User-agent: Claude-Code Disallow: / This instructs Claude Code Agent not to crawl any path on your site. To block only specific sections, replace / with the path (e.g., Disallow: /blog/).

Q: How do I verify if Claude Code Agent is crawling my site?

Search your access logs for Claude-Code (for example grep -i "Claude-Code" /var/log/nginx/access.log). Because the operator publishes no IP ranges or reverse-DNS pattern, a match shows that something used the name, not that Anthropic sent it.

Quick Facts

User-Agent:: Claude-Code
Category:: AI & LLM Bots
Operator:: Anthropic
Safety:: Safe
Blocking Impact:: Low - No SEO ranking impact
SEO Impact Score:: 2/10
Official docs:: None published by Anthropic
Named by:: ai.robots.txt

Reported, not operator documented

Anthropic has not published a crawler page that names Claude-Code. It is listed here because a credible public source does: ai.robots.txt. Claude Code agent fetches, reported in public registries. Anthropic publishes no UA for it.

What that means for you: the robots.txt rule on this page is the best available spelling, and a well-behaved crawler using this string will honour it, but there is no vendor statement of purpose, crawl rate or robots.txt compliance to rely on. Treat a matching request in your logs as a detection clue, not proof of who sent it, and combine the rule with a firewall rule if the traffic matters to you. If the operator publishes documentation, this profile moves to Official docs.

What is Claude Code Agent?

Claude Code Agent is an on-demand AI fetcher operated by Anthropic. It retrieves a page only when a user explicitly asks an AI assistant or agent to read, summarize, or act on a specific URL. Because it is triggered by real user intent rather than bulk crawling, blocking it mainly prevents users from pulling your content into Anthropic's assistant.

Claude Code Agent is an on-demand AI fetcher operated by Anthropic. It retrieves a page only when a user explicitly asks an AI assistant or agent to read, summarize, or act on a specific URL. Because it is triggered by real user intent rather than bulk crawling, blocking it mainly prevents users from pulling your content into Anthropic's assistant.
Claude Code Agent uses the user-agent token Claude-Code. You can control it via robots.txt, meta tags (noai), or the emerging llms.txt standard. Robots.txt is voluntary; for hard enforcement, combine it with server-level IP blocking.

What happens if you block Claude Code Agent?

✅ No SEO Impact - Blocking Claude Code Agent does not affect your rankings in Google, Bing, or any other search engine. Claude Code Agent is an AI crawler, not a traditional search indexer. You can freely block it via User-agent / Disallow: / without any SEO penalty.

Generally safe to allow; provides legitimate crawling value.

How to block Claude Code Agent with robots.txt

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

Block completely (robots.txt)

User-agent: Claude-Code
Disallow: /

Allow all (robots.txt)

User-agent: Claude-Code
Allow: /

Block private only (robots.txt)

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

Nginx server block

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

Apache .htaccess

# Apache: Hard-block Claude Code Agent
SetEnvIfNoCase User-Agent "Claude-Code" 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 Code Agent safe to allow?

Claude Code Agent is rated Safe in this directory, meaning there are no credible public reports of abusive crawling under this name. It is a Reported token: Anthropic has not published documentation for it, so its purpose, crawl rate and robots.txt behaviour are not confirmed by the operator, and anyone can send the same user-agent string. Allow or block it on its stated purpose, and back the robots.txt rule with a firewall rule if the traffic matters to you.

Anthropic publishes no IP ranges or reverse-DNS pattern for Claude Code Agent, so the user-agent string cannot be verified. Rate-limit unusual volume instead of trusting the name.

What does Claude Code Agent do?

Understanding Claude Code Agent's purpose helps you decide whether to allow or block it.

Fetches a page only when a user asks an AI assistant to read it
Summarizes or extracts the URL the user provided
Triggered by real user intent, not bulk crawling
Low traffic volume compared with training crawlers
Blocking it prevents users from pulling your content into the assistant

Frequently Asked Questions

What user-agent string does Claude Code Agent use?

Claude Code Agent is reported to identify itself with Claude-Code. That spelling comes from ai.robots.txt, not from Anthropic, which has not published crawler documentation naming it. Use it in robots.txt as the best available match, and treat a request carrying it as a clue rather than proof of who sent it.

Is Claude Code Agent safe?

Claude Code Agent is rated Safe in this directory, meaning there are no credible public reports of abusive crawling under this name. It is a Reported token: Anthropic has not published documentation for it, so its purpose, crawl rate and robots.txt behaviour are not confirmed by the operator, and anyone can send the same user-agent string. Allow or block it on its stated purpose, and back the robots.txt rule with a firewall rule if the traffic matters to you.

Will blocking Claude Code Agent hurt my SEO?

✅ No SEO Impact - Blocking Claude Code Agent does not affect your rankings in Google, Bing, or any other search engine. Claude Code Agent is an AI crawler, not a traditional search indexer. You can freely block it via User-agent / Disallow: / without any SEO penalty.

How do I block Claude Code Agent in robots.txt?

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

User-agent: Claude-Code
Disallow: /

This instructs Claude Code Agent not to crawl any path on your site. To block only specific sections, replace / with the path (e.g., Disallow: /blog/).

Does Claude Code Agent respect robots.txt?

Not documented. Anthropic has published no statement that Claude Code Agent reads robots.txt. A rule for Claude-Code will stop a client that chooses to honour it; for enforcement, add a firewall or CDN rule as well.

How do I verify if Claude Code Agent is crawling my site?

Search your access logs for Claude-Code (for example grep -i "Claude-Code" /var/log/nginx/access.log). Because the operator publishes no IP ranges or reverse-DNS pattern, a match shows that something used the name, not that Anthropic sent it.