How do AI Overviews and AI Mode choose sources?
Google's AI Overviews and AI Mode pick sources from Google's own search index, using the same ranking systems as regular results. Google says these features "are rooted in our core Search ranking and quality systems."
Google says AI Overviews "help people get to the gist of a complicated topic or question more quickly," and that AI Mode "is particularly helpful for queries where further exploration, reasoning, or complex comparisons are needed." Both show links to the pages that support their answers. They "may use different models and techniques," so their sources can differ, and AI Overviews "are only shown when our systems determine that it is additive to classic Search."
What is retrieval-augmented generation?
It's the main way these features find pages. Google describes retrieval-augmented generation, also called grounding, as "relying on our core Search ranking systems to retrieve relevant, up-to-date web pages from our Search index." The system then reviews information from those pages "to generate a more reliable and helpful response, showing prominent, clickable links to relevant web pages that support the information in the response."
In practice, a page that doesn't rank or isn't indexed has little chance of being retrieved.
What is query fan-out?
Query fan-out means the AI runs several related searches to answer one question. Google calls it "a set of concurrent, related queries generated by the model to request more information and fetch additional relevant search results."
Google's example: for "how to fix a lawn that's full of weeds," fan-out queries might include "best herbicides for lawns" and "how to prevent weeds in lawn." For a moving question such as "how to move a piano," related searches might cover cost, packing, and whether movers handle it. A page can be cited because it answers one of those related questions.
Google warns against chasing every variation. Creating separate content for fan-out queries "primarily to manipulate rankings or generative AI responses in Google Search violates Google's scaled content abuse spam policy."
What does a page need to be eligible?
Three technical conditions, per Google's guide:
- Indexed with a snippet. "A page must be indexed and eligible to be shown in Google Search with a snippet."
- Not excluded in Search Console. Google adds that "a site must be included in Search generative AI features in Search Console to be eligible for display." Inclusion is the default: Google calls it "the default control for all properties." A site drops out only if an owner chooses to exclude it under Settings > Search generative AI.
- Crawlable. Google says to "ensure your content is crawlable."
Meeting these doesn't guarantee anything. Google says: "Indexing and serving aren't guaranteed."
What helps a page get cited?
Google's answer is the same content quality its other ranking systems reward. It says content "that people find unique, compelling, and useful will likely influence your website's presence in generative AI search in the long run more than any of the other suggestions in this guide."
It singles out "non-commodity content": pages with "unique expert or experienced takes that go beyond common knowledge." A generic list of moving tips is commodity content. A page explaining how a specific company estimates a long-distance move, with real examples, is not.
For local businesses, Google says that "using products like Merchant Center (such as Merchant Center feeds) and Google Business Profiles can help your products and services to be visible in both AI responses and other Google Search results." See what is the map pack.
What doesn't help?
Google's guide lists things it says you can ignore for its search features:
- llms.txt and special files. Google Search "doesn't use them." See what is llms.txt.
- Chunking content into tiny pieces.
- Writing in a special style for AI.
- Special structured data. "There's no special schema.org markup you need to add."
How do you measure visibility in AI features?
Use Search Console. Google points site owners to "the Generative AI performance report in Search Console" to see how content performs in generative AI features on Google Search and Discover.
Google also cautions: "Be wary of third-party tools that promise ranking success or claim to use 'internal' Google metrics. No third-party tool has access to our internal ranking or AI systems."