anthropic-ai — Anthropic's Legacy Crawler

anthropic-ai is a deprecated crawler identifier associated with Anthropic, replaced by ClaudeBot. Learn whether you still need to block it in robots.txt.

QUICK FACTS

USER-AGENT anthropic-ai
OPERATOR Anthropic
CATEGORY Legacy / Deprecated
FIRST SEEN 2023-07
ROBOTS.TXT ✓ Respects directives
DOCUMENTATION Official docs →

What is anthropic-ai?

anthropic-ai is an older crawler identifier attributed to Anthropic that predates ClaudeBot. It is not listed in Anthropic's current official documentation but is still widely included in publishers' robots.txt files and appears in the community-maintained ai.robots.txt project on GitHub. Listing both anthropic-ai and ClaudeBot in your robots.txt costs nothing and covers older traffic that may still use the legacy identifier.

How to Block anthropic-ai

Add the following to your robots.txt file (located at the root of your website):

User-agent: anthropic-ai
Disallow: /

What Happens When You Block anthropic-ai

Blocks legacy Anthropic crawling. Modern crawling is handled by ClaudeBot — block both for complete opt-out from Anthropic training.

Should You Block anthropic-ai?

anthropic-ai is a legacy identifier that has been replaced by newer crawler names. Including it in your robots.txt is a best practice to catch older infrastructure that may still use the original identifier.

anthropic-ai vs Other Anthropic Crawlers

Anthropic operates multiple crawlers, each serving a different purpose:

User-agent Purpose Type
anthropic-ai Deprecated training crawler identifier Legacy / Deprecated
ClaudeBot Collects training data for Claude models AI Training
Claude-User Live page fetches triggered by Claude users User-Triggered Fetch
Claude-SearchBot Indexes content for Claude search results AI Search Index

Each crawler operates independently. Blocking anthropic-ai does not block ClaudeBot or Claude-User or Claude-SearchBot — you must add a separate rule for each.

GENERATE YOUR ROBOTS.TXT

Use our visual generator to create a robots.txt file that blocks anthropic-ai and any other crawlers you want to opt out of.