Definition
AI Overviews are the AI-generated summaries at the top of Google search results: an answer of a few paragraphs, written by Gemini from a set of pages, with links to those sources beside or below it. Google introduced them in May 2024 in the United States and then rolled them out to more than two hundred countries and dozens of languages, including Dutch. They now appear on a large share of informational and comparison queries.
An AI Overview comes about in three steps. Google splits the query into sub-questions (query fan-out), retrieves the best-fitting pages for each sub-question from the regular index and has Gemini write one answer from them, with the pages used as sources. There is no separate crawler and no separate index: whoever does not rank for one of the sub-questions does not make it into the sources. For navigational queries, news and sensitive topics, Google shows them less often.
The effect on traffic is large. Queries with an AI Overview produce noticeably fewer clicks on the classic results, because the answer is already on the page and the blue links move further down. At the same time, the cited sources get a visible spot at the top, even if they rank organically at position eight. Visibility therefore shifts from 'who is number one' to 'who gets cited', and that is a different contest.
Getting cited calls for pages that contain a direct, factual answer per sub-question in readable HTML, with clear headings, current information and a recognisable author. You cannot opt out of AI Overviews separately: they use the same Googlebot as the regular results, and blocking Google-Extended has no effect on them. The nosnippet and max-snippet directives do limit what Google may show from your page — at the price of disappearing from the summary as well.
Measuring is hard because Search Console does not report clicks and impressions from AI Overviews separately. If you want to know whether you are cited, you have to fetch the results yourself periodically for a fixed set of queries and record per query which sources appear. Traze does that per keyword cluster and shows for which questions a competitor sits in the summary and you do not.