AI VISIBILITY · SEO GLOSSARY
llms.txt
A plain-text file at the root of a domain that guides AI systems to a site's most useful and citeable pages.
Definition
llms.txt is an emerging convention for a plain-text file at `yourdomain.com/llms.txt` that provides AI language models with a curated, citable overview of a website. It typically includes the site name, a short description, a list of key URLs with brief summaries, and optionally a link to a more detailed `llms-full.txt`. The convention was proposed by Jeremy Howard in 2024 and has been adopted by Perplexity and other AI retrieval systems.
Why it matters for SEO
AI systems that retrieve web content before generating answers need to quickly understand what a site is about and which pages are most useful. llms.txt provides that map in a standardized, machine-readable format that is simpler than parsing a full sitemap. A missing llms.txt is not a disqualifying signal, but it is a missed opportunity — especially for sites with content that AI systems should be citing.
How DeepSEOAnalysis checks this
The audit checks whether `yourdomain.com/llms.txt` exists and returns a 200 status. If missing, it is flagged as an info-level AI-visibility gap. If present, the audit checks that it is a valid plain-text file with a non-empty body. The llms.txt generator tool creates a correctly formatted file from your site name, description, and key pages.
Useful tools and resources
GLOSSARY
Related terms
ai visibility
Generative Engine Optimization (GEO)
The practice of structuring content so that AI-powered answer engines can retrieve, understand, and cite it in generated responses.
Read definition →technical
Robots.txt
A text file at the root of a domain that tells crawlers which pages or sections to access or avoid.
Read definition →See how your site scores on llms.txt.
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