Model training · Anthropic
anthropic-ai
An older Anthropic token that still appears in many robots.txt files. Anthropic's current documentation lists only ClaudeBot, Claude-SearchBot and Claude-User.
- Operator
- Anthropic
- Purpose
- Model training
- Used for
- Legacy token
- Obeys robots.txt
- Unclear
- robots.txt token
anthropic-ai- User-agent string
- Not published by the operator
- IP list
- Not published
- Official docs
- None published
Block anthropic-ai in robots.txt
User-agent: anthropic-ai
Disallow: /Well-known sites that block anthropic-ai
yahoo.com #72, msn.com #92, chatgpt.com #112, snapchat.com #157, tumblr.com #160, nytimes.com #163, ebay.com #191, cnn.com #195, theguardian.com #196, bbc.com #216, sciencedirect.com #224, bbc.co.uk #236, canva.com #276, nature.com #297, trustpilot.com #344, espn.com #363, washingtonpost.com #383, bloomberg.com #386, aol.com #421, businessinsider.com #471, cnbc.com #474, behance.net #525, uol.com.br #535, ft.com #552
Other Anthropic bots
ClaudeBot (model training) · Claude-SearchBot (ai search index) · Claude-User (user-triggered fetch) · Claude-Web (user-triggered fetch)
Questions
What is anthropic-ai?
anthropic-ai is a model training bot operated by Anthropic, used for Legacy token. An older Anthropic token that still appears in many robots.txt files. Anthropic's current documentation lists only ClaudeBot, Claude-SearchBot and Claude-User.
How do I block anthropic-ai?
Add "User-agent: anthropic-ai" followed by "Disallow: /" to the robots.txt file at the root of each host you want to protect.
Does anthropic-ai respect robots.txt?
Anthropic has not clearly documented whether anthropic-ai honours robots.txt.
How many websites block anthropic-ai?
In a Oct 29, 2026 analysis of the top 10,000 websites by Kuldeep Paul, 14.8% of sites with a robots.txt file fully disallowed anthropic-ai.
Analysis using this data
- Who blocks AI crawlers? What 10,000 robots.txt files revealPublishers block training, not answers; half of all blocklists leak; Cloudflare writes the most common AI policy.
- The opt-out asymmetry: you can block the small AI engines, not the big oneThe AI surfaces with the most users are the ones publishers can't refuse and can't measure.
How to cite this data
This dataset is free to use, including commercially, under Creative Commons Attribution 4.0. The one rule is attribution:
- Credit the source as “Kuldeep Paul, kuldeep.cc” wherever you use a figure, chart or table from it.
- Link to this page (https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai), not to the download file, so readers can check the source of every number.
- Include the date. These figures change; say “as of Oct 29, 2026” or link to the version you used.
- Mark changes. If you filter, recalculate or chart the data yourself, say so (“analysis based on data from…”).
- Cite the original source for single figures when you quote one reported number; it is linked in every row.
In running text: according to Kuldeep Paul's anthropic-ai — AI crawler directory (kuldeep.cc). More in the methodology.
Paul, K. (2026). anthropic-ai — AI crawler directory [Data set]. kuldeep.cc. https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai
Paul, Kuldeep. "anthropic-ai — AI crawler directory." kuldeep.cc, 29 October 2026, https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai.
Paul, Kuldeep. 2026. "anthropic-ai — AI crawler directory." Dataset. kuldeep.cc. Updated Oct 29, 2026. https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai.
@misc{paul2026anthropicai, author = {Paul, Kuldeep}, title = {anthropic-ai — AI crawler directory}, year = {2026}, howpublished = {\url{https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai}}, note = {Dataset, CC BY 4.0, updated 2026-10-29} }
<a href="https://kuldeep.cc/data/ai-search/crawlers/anthropic-ai">anthropic-ai — AI crawler directory</a> (data: Kuldeep Paul, kuldeep.cc)