Generative engine optimization (GEO): what is documented, what was studied and what is guesswork

Generative engine optimization, or GEO, is the work of getting a site's pages linked or quoted in the answers that AI assistants and search engines write. AEO, "AI SEO" and "AI search optimization" are other names for the same work, and Google's own guide says it is still SEO.

What the engines themselves document is short. Their search crawlers have to be able to reach the page. For Google, the page has to be indexed and eligible to be shown with a snippet. Microsoft adds that the answer should sit in visible text under a clear heading. Much of what is advised beyond that rests on a single study, or on nothing an engine has said. This page puts each claim in one of three standings and gives the source for every one.

What GEO, AEO and AI SEO mean

• GEO is generative engine optimization. The name was introduced in a research paper first posted in November 2023.
• AEO is answer engine optimization.
• AI SEO and AI search optimization are plain words for the same thing.

Google's guide says GEO and AEO are both used for work aimed at being visible in AI search.

Google takes neither as its own term. It writes "generative AI features" for AI Overviews and AI Mode, and its guide says: "From Google Search's perspective, optimizing for generative AI search is optimizing for the search experience, and thus still SEO."

Microsoft uses GEO. Bing's Webmaster Guidelines say it is about a page's eligibility to ground and be referenced in AI answers, and open by saying that the fundamentals of SEO still apply, because Bing and Copilot rest on the same crawling, indexing and ranking.

The three standings

• Documented. An engine or a platform says so on its own page.
• A study. Someone measured it. Who ran it, on what, when, and whether they sell something in this trade all matter. A correlation is not a cause.
• Guesswork. Said widely and documented by nobody.

No claim is moved up a standing here. Each statement carries its source's date where there is one, and everything below is as its source read on October 8, 2026.

What the engines document

Google

• Requirements. Google's page on AI features says there are no additional requirements to appear in AI Overviews or AI Mode. To be shown as a supporting link, a page must be indexed and eligible to be shown in Search with a snippet.
• What a site can ignore. Google's guide, published on May 15, 2026, and updated on July 10, 2026, lists what a site does not need for Google Search: llms.txt and other machine-readable files, content split into small chunks, pages rewritten for AI systems, and special markup. Structured data is not required, and there is no special schema.org markup to add. A note added on June 15, 2026, says an llms.txt file neither harms nor helps.
• What it says matters most. Content that people find unique and useful will likely do more for a site's presence in generative AI search than anything else the guide suggests.
• Snippet controls count. Google's robots tag documentation says nosnippet prevents a page's content from being used as a direct input for AI Overviews and AI Mode, and max-snippet limits how much may be used.
• A report. Search Console's Generative AI performance report was announced on June 3, 2026, for a subset of sites and, its help page says, rolled out to all websites as of August 31, 2026. It gives impressions in AI Overviews and AI Mode by page, country, date or device. Queries are not among its groupings, and a site with too few impressions sees no report.
• A way out. In Search Console, under Settings, then "Search generative AI", a property is included in AI Overviews, AI Mode and the generative AI features in Discover, or excluded from them. Included is the default, and a property under a parent follows its parent. The help page says the control is rolled out to all websites as of August 31, 2026, and that the choice is not a ranking signal for other parts of Search. Google's guide lists being included among the conditions for appearing.
• Spam policies apply. Since a clarification of May 15, 2026, the spam policies name attempts to manipulate generative AI responses in Search beside attempts to manipulate ranking.

How to appear in Google's AI Overviews goes through Google's side in full.

Microsoft: Bing and Copilot

Microsoft is specific about how to write a page, in a guide of October 8, 2025, and in Bing's Webmaster Guidelines, which carry no date.

• How Copilot reads. The guide says Copilot breaks a page into pieces and builds an answer from pieces of several pages.
• What to write. A title, a description and a top heading that agree. Headings that mark where one idea ends and the next begins. Questions with direct answers of one or two sentences that still make sense when lifted out of the page. Lists and tables for steps and comparisons. The guidelines add: key information near the top, one subject to a page, and facts stated on the page itself.
• What to avoid. Long walls of text, key facts that exist only in an image or a PDF, and answers placed in tabs or expandable menus, because its systems may not render hidden content.
• Directives. The guidelines say noindex keeps a page out of Bing search and Copilot, noarchive prevents its content from being used in Copilot's responses, nocache limits Copilot to the address, title and snippet, and nosnippet may limit the quality of a citation.
• Structured data. It may support clearer grounding, must match the visible content, and does not guarantee visibility.
• Abuse. The guidelines list cloaking, wording engineered to trigger citations, and content added to manipulate the AI models behind Bing or Copilot.
• A report. AI Performance in Bing Webmaster Tools opened as a public preview on February 10, 2026. It counts citations across Copilot, AI summaries in Bing and some partner products, by page, and shows grounding queries: the key phrases the system used to retrieve what it cited. Its help page says these are not a person's full question. On June 16, 2026, Microsoft added Intents, Topics, Citation Share and Compare, still in preview.
• IndexNow. Microsoft recommends this protocol for telling search engines that a page changed. The protocol's FAQ lists endpoints for Amazon, Bing, Naver, Seznam.cz, Yandex and Yep. Google is not on that list.

OpenAI, Anthropic and Perplexity

Each company publishes the names its crawlers answer to in robots.txt.

• OpenAI. The rules for OAI-SearchBot and GPTBot are independent. A site that disallows OAI-SearchBot is not shown in ChatGPT's search answers, though it can still appear as a navigational link. A change to robots.txt takes about 24 hours to reach its search systems. Of ChatGPT-User, the page says robots.txt rules may not apply, because a person started the request.
• Anthropic. Its page says its bots honor robots.txt, and that it supports the non-standard Crawl-delay line. Blocking Claude-SearchBot or Claude-User, it says, may reduce a site's visibility in search results and in answers to a person's request.
• Perplexity. Its page recommends allowing PerplexityBot in order to appear in its search results, and says that crawler is not used to collect content for training foundation models. Perplexity-User, it says, generally ignores robots.txt because a person asked for the fetch. A change can take up to 24 hours.

OpenAI and Perplexity both recommend more than a robots.txt rule: requests from their published IP ranges should be allowed too, which is a matter for a firewall, a CDN or a host. None of the three pages says what makes a page chosen for an answer.

Blocking or allowing AI crawlers on WordPress covers the rules and what can stop a crawler before WordPress is asked. WordPress robots.txt covers the file itself.

What studies have found

Four of these five come from companies that sell software for tracking AI answers. Each finding is given as its authors state it.

The first, second and fourth are correlations. They show which pages were cited at one time, and not why. The third compared matched pages before and after a change, which is stronger, and found nothing clear. The fifth is a laboratory benchmark, and the Perplexity it tested is the one of that time.

What is guesswork

Each of these is sold or advised, and documented by no engine as a way to be cited.

A checklist for a WordPress site

If you would rather hand this list to someone, WP Ministry does this kind of work as AI search optimization. What is sold is the work, never a citation.

What nobody can promise

No engine promises a citation. Google's page on AI features says a page that meets every requirement may still not be crawled, indexed or served. Bing's guidelines say SEO does not guarantee rankings or traffic and GEO does not guarantee grounding or citations.

Google published guidance on June 5, 2026, for anyone buying this work, and it names "AEO" and "GEO" tools and services directly:

• Tools. "Third-party tools don't have access to our internal ranking data."
• Advice. Good advice either presents a claim as opinion based on data or experience, or backs it with official guidance.
• Sellers. Its page on hiring an SEO gives a buyer questions to ask, among them: "Do they cite official Google documentation as supporting evidence for their recommendations?" It also asks whether advice on AI search agrees with Google's own guide, and says no one can guarantee a first-place ranking.