Free glossary
AI search glossary
Every AI search term, in one plain line.
This AI search glossary explains the terms you'll hear about getting found in ChatGPT, Claude, Gemini, Perplexity, Copilot and Google's AI Overviews, in one plain sentence each. It covers the names for the work (AEO, GEO, LLM SEO), Google's AI features, how assistants find answers, the AI crawlers, and agents and MCP.
Many of these terms describe the same job: making your business easy for AI to find, trust and name.
AI search glossary: the names for the work
Different people use different names for much the same thing. The work behind them overlaps almost completely.
| Term | What it means |
|---|---|
| AI search | Getting answers from an AI assistant or an AI-written summary, rather than a list of links. |
| AI SEO | Search optimisation for AI assistants as well as Google: making your business easy for them to find, trust and name. |
| AEO | Answer engine optimisation: making your page the direct answer a search engine or assistant gives to a question. |
| GEO | Generative engine optimisation: showing up in answers that AI writes from search results. The term comes from a 2023 research paper. |
| LLM SEO | Making sure large language models such as ChatGPT, Claude and Gemini know your business and name it when it's relevant. |
| AI visibility | How often, and how accurately, AI assistants mention your business for the questions your buyers ask. |
| Prompt tracking | Asking assistants the same buyer questions every month and logging who gets named. |
| Entity | A thing search engines and assistants recognise as distinct, such as your business, a person or a place. |
| Entity SEO | Making the facts about your business clear and consistent everywhere, so it's recognised as one entity. |
What do Google's AI search terms mean?
Google runs AI features inside its normal search results, using its normal index.
| Term | What it means |
|---|---|
| AI Overviews | AI-written summaries that appear above the normal Google results for some searches, with links to the pages they draw on. |
| AI Mode | Google's conversational search, where people can ask follow-up questions and get AI-written answers. |
| Query fan-out | Google running several related searches behind the scenes to build an AI answer, which is why it can cite pages that don't rank for the exact search. |
| Gemini | Google's AI assistant and the family of models behind its AI features. |
| Zero-click search | A search where the answer appears in the results and the person doesn't click through to a site. |
| Featured snippet | A short answer from one page shown at the top of Google's results. |
How do AI assistants find their answers?
Assistants answer from what they learned in training, from live web searches, or both.
| Term | What it means |
|---|---|
| LLM | Large language model: the AI system behind tools such as ChatGPT, Claude and Gemini. |
| Training data | The text a model learned from before release. Facts in it can be months or years out of date. |
| Live search | When an assistant searches the web while answering, so it can use current pages. |
| Retrieval (RAG) | Retrieval-augmented generation: fetching relevant pages or documents first, then writing the answer from them. |
| Grounding | Tying an AI answer to real sources, so it can cite where each claim came from. |
| Citation | A link or source an assistant shows alongside its answer. |
| Hallucination | When an AI states something that isn't true, such as a wrong price or an old address. |
| Schema markup | Structured data on a page that states facts like your name, address, services and FAQs in a form machines read easily. |
| llms.txt | A plain-text summary of a site with links to its key pages, proposed at llmstxt.org in 2024. Optional, and not a ranking factor. |
| llms-full.txt | A longer companion to llms.txt with fuller text from a site's key pages. |
| AI referral traffic | Visits to your site from assistants, such as chatgpt.com or perplexity.ai, which you can track in analytics. |
Which AI crawlers should you know?
Crawlers are the bots that read your site. Some feed search answers, some feed model training, and you can treat them differently in robots.txt.
| Crawler | Who runs it, and what it's for |
|---|---|
| Googlebot | Google. Crawls for Google Search, including AI Overviews and AI Mode. |
| Google-Extended | Google. A robots.txt control for whether your content is used for Gemini. It doesn't affect Google Search. |
| Bingbot | Microsoft. Crawls for Bing, which Copilot uses. |
| OAI-SearchBot | OpenAI. Crawls for ChatGPT search results. |
| GPTBot | OpenAI. Crawls for model training. |
| ChatGPT-User | OpenAI. Visits a page when a ChatGPT user's request needs it. |
| Claude-SearchBot | Anthropic. Crawls to improve Claude's search results. |
| ClaudeBot | Anthropic. Crawls for model training. |
| Claude-User | Anthropic. Visits a page when a Claude user's request needs it. |
| PerplexityBot | Perplexity. Crawls for Perplexity's search results. |
| Perplexity-User | Perplexity. Visits a page when a Perplexity user's request needs it. |
| robots.txt | The file at the root of your site that tells crawlers which pages they may visit. |
| IndexNow | A way to tell Bing and other search engines straight away when pages are added or changed. |
What do agents and MCP mean?
Assistants are starting to take actions, not just answer questions. These are the terms for that.
| Term | What it means |
|---|---|
| AI agent | An AI that carries out tasks for someone, such as comparing quotes or booking a slot, not just answering. |
| MCP | Model Context Protocol: an open standard, published by Anthropic in November 2024, for connecting AI assistants to outside tools and data. |
| MCP server | A small piece of software that lets assistants such as ChatGPT and Claude connect to a business and take actions, like getting a quote or checking an order. |
| Connector | A link between an assistant and an outside service, often built on MCP. |
| Agent-ready website | A site an AI agent can read and act on: clear facts, prices, availability and a way to book or buy. |
How does Foundry approach AI search?
Whatever the name, the work is the same: clear facts on your own site, open access for the right crawlers, consistent listings, reviews, press, and a monthly check of what assistants actually say.
That's what we do in our AI SEO work. For BidScript, it meant 40x more Google AI answers in 3 months. Where a business wants assistants to take actions, we build MCP connectors and integrations.
Our averages. Not our best days.
Our averages
5days
Website, kick-off to live
3hours
Google Ads setup
4hours
Meta Ads setup
7days
To a first PR feature
20mins
Average reply timethis service
AI search glossary FAQs
Barely. AEO is about being the direct answer, GEO about appearing in AI-written answers, and LLM SEO about language models knowing your business. The work behind them is the same.
It builds on it. Assistants read pages that rank in search, so SEO still matters. AI SEO adds the facts, listings and checks that matter most for being named in an answer.
Blocking search crawlers such as OAI-SearchBot or Claude-SearchBot can keep you out of those assistants' answers. Training crawlers are a separate choice. Our robots.txt AI checker shows what you're allowing.
Most small businesses don't yet. It's worth it when buyers would benefit from an assistant getting a quote, booking or checking an order for them.
No. Assistants can read your normal pages without it. It's a cheap, optional extra.
In our glossary of marketing terms: SEO, PPC, CTR, CPA, ROAS, CRO and more.
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