Anthropic AI (Deprecated): User Agent & robots.txt Rules

Q: Is Anthropic AI (Deprecated) safe?

Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) hurt my SEO?

✅ No SEO Impact - Blocking Anthropic AI (Deprecated) does not affect your rankings in Google, Bing, or any other search engine. Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) in robots.txt?

Add the following lines to your /robots.txt file: User-agent: anthropic-ai Disallow: / This instructs Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) is crawling my site?

Search your access logs for anthropic-ai (for example grep -i "anthropic-ai" /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:: anthropic-ai
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 anthropic-ai. It is listed here because a credible public source does: ai.robots.txt. Legacy Anthropic token from before ClaudeBot. Anthropic no longer documents it; registries and older robots.txt files still carry 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 Anthropic AI (Deprecated)?

Anthropic AI (Deprecated) is an AI data-collection crawler operated by Anthropic. It gathers public web content to build or refine training datasets for large language models. Like other AI training crawlers, Anthropic AI (Deprecated) does not influence your search-engine rankings, so you can block it via robots.txt without any SEO penalty if you wish to opt out of AI training.

Anthropic AI (Deprecated) is an AI data-collection crawler operated by Anthropic. It gathers public web content to build or refine training datasets for large language models. Like other AI training crawlers, Anthropic AI (Deprecated) does not influence your search-engine rankings, so you can block it via robots.txt without any SEO penalty if you wish to opt out of AI training.
Anthropic AI (Deprecated) uses the user-agent token anthropic-ai. 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 Anthropic AI (Deprecated)?

✅ No SEO Impact - Blocking Anthropic AI (Deprecated) does not affect your rankings in Google, Bing, or any other search engine. Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) with robots.txt

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

Block completely (robots.txt)

User-agent: anthropic-ai
Disallow: /

Allow all (robots.txt)

User-agent: anthropic-ai
Allow: /

Block private only (robots.txt)

User-agent: anthropic-ai
Disallow: /private/
Disallow: /api/
Disallow: /admin/
Allow: /

Nginx server block

# Nginx: Hard-block Anthropic AI (Deprecated)
if ($http_user_agent ~* "anthropic-ai") {
    return 403 "Bot blocked";
}

Apache .htaccess

# Apache: Hard-block Anthropic AI (Deprecated)
SetEnvIfNoCase User-Agent "anthropic-ai" 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 Anthropic AI (Deprecated) safe to allow?

Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated), so the user-agent string cannot be verified. Rate-limit unusual volume instead of trusting the name.

What does Anthropic AI (Deprecated) do?

Understanding Anthropic AI (Deprecated)'s purpose helps you decide whether to allow or block it.

Collects public web content to train large language models
Builds and refreshes AI training datasets
Harvests text, code, and structured data for model improvement
Does NOT affect search-engine rankings
Can be blocked to opt out of AI training without SEO loss

Frequently Asked Questions

What user-agent string does Anthropic AI (Deprecated) use?

Anthropic AI (Deprecated) is reported to identify itself with anthropic-ai. 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 Anthropic AI (Deprecated) safe?

Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) hurt my SEO?

✅ No SEO Impact - Blocking Anthropic AI (Deprecated) does not affect your rankings in Google, Bing, or any other search engine. Anthropic AI (Deprecated) 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 Anthropic AI (Deprecated) in robots.txt?

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

User-agent: anthropic-ai
Disallow: /

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

Does Anthropic AI (Deprecated) respect robots.txt?

Not documented. Anthropic has published no statement that Anthropic AI (Deprecated) reads robots.txt. A rule for anthropic-ai will stop a client that chooses to honour it; for enforcement, add a firewall or CDN rule as well.

How do I verify if Anthropic AI (Deprecated) is crawling my site?

Search your access logs for anthropic-ai (for example grep -i "anthropic-ai" /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.