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anthropic-ai — Anthropic legacy token

anthropic-ai is a historical robots.txt token associated with Anthropic's earlier crawling, now superseded by ClaudeBot. Anthropic's current guidance centres on ClaudeBot and its user-triggered fetcher. Keeping a legacy rule is harmless but the active control is ClaudeBot.

Partially verified

What this means

anthropic-ai is a historical robots.txt token associated with Anthropic's earlier crawling activity. Anthropic's current public guidance centres on ClaudeBot for background crawling, plus user-triggered fetch tokens such as Claude-User.

This matters for robots.txt hygiene: a rule targeting anthropic-ai is not wrong to keep, but it is the legacy name. To control Anthropic's present-day crawling, target ClaudeBot. Where the exact history of the token is not fully documented, this entry stays conservative rather than guessing.

Migration to ClaudeBot

If your robots.txt contains a legacy anthropic-ai rule, the practical migration is to add or maintain a ClaudeBot rule that reflects your intended policy:

User-agent: ClaudeBot Disallow: /

You can keep the older anthropic-ai rule alongside it; an unused token rule is harmless. The active, documented control for Anthropic crawling today is ClaudeBot, with separate tokens for user-triggered fetches.

How it appears in analytics and logs

Seeing anthropic-ai in older robots.txt files reflects an earlier Anthropic token. Current Anthropic crawling is documented under ClaudeBot, so treat anthropic-ai as historical and verify present-day activity against the ClaudeBot token.

Diagnostic use case

Understand legacy anthropic-ai robots.txt rules and migrate to controlling ClaudeBot, which is Anthropic's current crawler token.

What WebmasterID can help detect

WebmasterID classifies current Anthropic crawling under ClaudeBot. The legacy anthropic-ai token is historical; WebmasterID surfaces the crawlers it actually observes rather than deprecated token names.

Common mistakes

Privacy and accuracy notes

This entry concerns robots.txt tokens, not visitor data. A legacy token in your robots.txt is a policy artefact and involves no human identity. WebmasterID records any current crawl as a bot event only.

Related pages

Sources and verification notes

Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.