GEO & AI search glossary
llms.txt
What is llms.txt and do I need one?
A plain-text file at the root of a site that summarizes what the site is and points AI systems to its most important pages. This site publishes one at /llms.txt and a longer version at /llms-full.txt.
The format is a markdown-flavoured text file at /llms.txt: what the site is, who runs it, the canonical facts about the business, and a curated list of the pages that matter with a sentence on each. A longer companion file at /llms-full.txt carries the expanded version.
No engine is contractually obliged to read it, and it is not a ranking factor. What it does is remove ambiguity cheaply — a single authoritative statement of your facts, in the plainest possible format, at a predictable URL. It costs nothing to publish and it is trivially easy to keep accurate.
Related terms
- Answer Engine Optimization (AEO)Optimizing a page to be the single extracted answer a search engine shows or reads aloud — featured snippets, People Also Ask entries, voice assistant replies. AEO is about owning the snippet; GEO is about being named inside a generated answer.
- AI crawlerA bot operated by an AI company that fetches web pages for training or for live retrieval — GPTBot, OAI-SearchBot, ClaudeBot, Google-Extended, PerplexityBot and others. Blocking them in robots.txt removes you from the answers they generate.
- Structured data (schema markup)Machine-readable JSON-LD embedded in a page that states what the page is about, who published it and how its entities relate. It does not force a citation, but it removes ambiguity about who you are.
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