What is Google-Extended?

Google-Extended is a standalone product token that you use in robots.txt to control whether content Google crawls may be used to train future Gemini models and for grounding in Gemini Apps and Vertex AI. It is not a crawler and has no user agent of its own. Google says it does not affect inclusion or ranking in Google Search.

At a glance

Operator
Google
Type
robots.txt product token (not a crawler)
HTTP user agent
None. Crawling uses Google's existing user agents
Controls
Gemini model training, and grounding in Gemini Apps and Vertex AI
Effect on Google Search
None. Google says it is not used for inclusion or as a ranking signal
Status
Google says it intends to support the AIPREF training preference signal in early 2027

How it works

  • It is a rule, not a visitor: you add User-agent: Google-Extended to robots.txt. Googlebot still crawls your pages as usual. The token only tells Google how that content may be used.
  • What it covers: training future Gemini models, and grounding (giving content from the Google Search index to a model at prompt time) in Gemini Apps and Grounding with Google Search on Vertex AI.
  • What it does not cover: inclusion or ranking in Google Search. For how your content appears in Search, Google points to controls such as nosnippet, max-snippet and noindex.
User-agent: Google-Extended
Disallow: /

Related Google crawlers and controls

Quick answers

Does blocking Google-Extended hurt my Google rankings?

No. Google says Google-Extended does not affect a site's inclusion in Google Search and is not used as a ranking signal.

Does blocking Google-Extended keep me out of AI Overviews?

Google does not say so. Its AI features documentation points to Search controls such as nosnippet and noindex for Search, and to Google-Extended for training and grounding in other systems.

Why do I see Google-Extended in my logs?

Because someone is faking it. Google says Google-Extended has no separate HTTP request user agent, so a real request never carries it.

Sources