What is llms.txt?
llms.txt is a proposed plain-text file at a site's root that gives AI systems a curated, machine-readable summary of the site's most important content. It is a convention, not a standard: Google says its Search does not use it, and 2026 studies found most llms.txt files are never requested, though some coding agents read them.
Why llms.txt matters
An llms.txt file is a Markdown document at the site root that tells language models what the site is, what it offers and where the important pages are, in a form they can read without parsing navigation, scripts and cookie banners. It was proposed by Jeremy Howard in 2024 and is a convention rather than a standard. In 2026 Google stated that its Search does not use llms.txt, and an Ahrefs study of 137,000 domains found 97% of these files received no requests at all; some coding agents and documentation tools do read them. So it costs nothing to publish, but it will not move your AI visibility on its own: crawler access, quotable answers on your pages and third-party mentions matter far more. A companion llms-full.txt can carry the full text of your key documentation.
Its real value is forcing clarity. Writing the file means stating in plain words who you are, what the product does, who it is for and what it costs, which is exactly the passage a model needs to describe or recommend you. Keep it current, link the canonical pages, and mirror the same facts on the About page and in Organization structured data so every source agrees.
Example
The opening of a good file:
# Webmatik
> AI website audit tool: 70+ checks in 8 categories, including
> AI search visibility. Free checks; full audits from $2.
## Key pages
- Pricing: https://webmatik.ai/pricing
- API docs: https://webmatik.ai/api-docsA blockquote summary first, then the pages that matter, all as absolute URLs.
Common mistakes
- •Publishing it once and letting prices and features drift.
- •Filling it with marketing slogans instead of facts a model can repeat.
- •Blocking AI crawlers in robots.txt, which stops them reading the file you wrote for them.
How Webmatik checks it
The AI discovery file (llms.txt) check fetches /llms.txt, confirming with a GET request because some servers wrongly reject HEAD requests; on paid plans the Fix Pack drafts an llms.txt from the audited site's own content.
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