What is Google-Extended?

Google-Extended, explained

Google-Extended isn't a crawler. Google's documentation says crawling is done with existing Google user agents, and the Google-Extended token is used in a control capacity. You write rules for it in robots.txt like any other bot, but no requests ever arrive with that name in your logs.

What it controls: whether content Google crawls from your site may be used for training future generations of Gemini models, and for grounding, which Google defines as providing content from the Google Search index to the model at prompt time to improve factuality and relevancy. Google lists the products it covers: Gemini Apps, the Vertex AI API for Gemini, and Grounding with Google Search on Vertex AI.

What it doesn't control: Google Search. Google states that Google-Extended does not affect a site's inclusion in Google Search and is not used as a ranking signal. AI Overviews and AI Mode are part of Search, so blocking Google-Extended doesn't remove you from them. To keep a whole site out of them, use the Search generative AI control in Search Console (Settings > Search generative AI), rolled out to all websites by August 31, 2026. Google says that control isn't a ranking or inclusion signal for the rest of Search. Snippet rules like nosnippet or max-snippet limit single pages, but they change your regular results too.

The two controls split the job. Google's help page for the Search Console control says it doesn't affect AI training, and points to Google-Extended to limit training of the models used to generate responses in those features. So the control decides whether your pages appear in Google's AI answers, and Google-Extended decides whether your content trains and grounds Gemini.

So the decision is narrower than it looks. Blocking Google-Extended keeps your content out of Gemini training and Gemini's grounding. It won't cost you Google rankings, but it can mean Gemini is less likely to use or cite your pages in answers that rely on grounding.

Apple has a similar control token, Applebot-Extended, for its AI training. Both follow the same pattern: the normal crawler keeps crawling for search, and the extra token decides AI use.

Why it matters for founders

Founders often block Google-Extended thinking it keeps them out of AI Overviews, or avoid blocking it fearing SEO damage. Neither is right. Knowing what it does lets you make the trade-off on purpose.

Example

A publisher adds User-agent: Google-Extended / Disallow: /. Its pages keep ranking and appearing in AI Overviews, but Google won't use them for Gemini training or grounding.

Common mistakes

• Expecting it to remove your site from AI Overviews. That's the Search Console control's job.
• Worrying that blocking it hurts Google rankings. Google says it doesn't.
• Looking for Google-Extended requests in server logs.
• Blocking Googlebot instead, which removes you from Search entirely.