Deep dive · XiaoHu Explains

How Should Websites Optimize in the AI Search Era? Google's Official SEO Guide

Google Search just gave its first systematic take on optimizing sites for AI Overviews and AI Mode—and called out a pile of AEO/GEO buzzwords by name along the way.
One-minute rundown
  • Google Search's own team, Search Central, published a guide on getting sites cited more often in generative AI search features like AI Overviews and AI Mode.
  • The core takeaway: classic SEO best practices still hold, because these AI features are built on top of Google's core search ranking systems. From Google's perspective, optimizing for AI search just means optimizing the search experience—it's still SEO.
  • Google explicitly named a batch of popular tactics you don't need to bother with: special files like llms.txt (Google Search doesn't read them), chunking content into small pieces, rewriting content specifically for AI, faking mentions, and piling on structured data.
  • Two mechanisms decide how AI uses your content: RAG (retrieval-augmented generation, also called grounding) retrieves web pages first, then generates an answer with links; query fan-out splits one question into multiple related queries searched in parallel.
  • What actually matters hasn't changed: write content with a distinct point of view that isn't available everywhere, keep a clean technical structure, add good images and video, then check the results in Search Console.
This is Google Search's own guide (from Search Central), so it reflects Google's side of things. Alongside its recommendations, it's also passing judgment on third-party standards and services like llms.txt and AEO/GEO—worth remembering this is Google talking its own book.
1Background

AI search threw the SEO world into chaos. Google just stepped in to settle it.

Google Search's team, Search Central, published a guide specifically on getting sites cited more effectively in its generative AI search features. That means AI Overviews, the AI-generated summary at the top of search results, and AI Mode, its conversational search experience.

More people are now asking AI directly for answers instead of clicking through blue links one by one. Over the past six-plus months, that shift has set the SEO and content world on edge: new terms and even new industries have sprung up around AEO (answer engine optimization) and GEO (generative engine optimization), and some are pushing new file standards like llms.txt, written specifically for AI to read. The anxiety underneath it all is hard to avoid: after years of grinding away at SEO, is all of it about to be worthless?

Google just said it plainly: in the age of AI search, SEO isn't obsolete—and a lot of the new "AI optimization" tactics floating around are a waste of effort.
🎯Why this matters: this is the first time Google Search has laid out a systematic set of best practices for generative AI search, and it names llms.txt, AEO, and GEO—all the hyped-up tactics of the moment—one by one. This is Google's own first-hand word, not a third-party blog's guesswork.
2Mechanics

Why SEO isn't obsolete: AI search still runs on the ranking system

The logic is simple: these generative AI features are rooted in Google's existing core search ranking and quality systems. AI stands on the foundation SEO already built, picking and using content through two mechanisms—it didn't start from scratch with some new way of understanding web pages.

RAG: the AI looks things up before it answers

RAG stands for retrieval-augmented generation; Google also calls it grounding. Here's what it means: before answering you, the AI leans on the core ranking system to retrieve relevant, sufficiently fresh pages from Google's index, reviews the specifics on those pages, then generates a more reliable answer—complete with clickable, prominent links back to those pages.

User's question
Core ranking system
retrieves relevant pages
from the index
AI reviews
the specific details
on these pages
Generates an answer
with clickable links

That chain has a direct implication: whatever AI cites in its answers comes from pages that were crawled and indexed. If your page never makes it into the index, AI can't use it in an answer either. So the old SEO homework—being crawlable, being indexable—hasn't been rendered obsolete by AI search at all.