llms.txt: What It Is and Whether You Need One

A plain-text file that tells language models what your site contains and where the important content lives.

What it does

llms.txt sits at your domain root and provides a structured, markdown-formatted summary of your site: what you do, what your key pages are, and how they relate. It is conceptually similar to a sitemap but written for language models rather than crawlers.

Whether it matters yet

Adoption is uneven and no major model provider has committed to it as a formal standard. The honest position is that it may help, costs almost nothing to implement, and carries no downside.

Treat it as cheap insurance rather than a decisive tactic.

How to write one

Open with a one-paragraph description of what your organisation does. List your primary sections with links and short descriptions. Include key facts a model might need to answer questions about you accurately. Keep it current, because a stale file is worse than none.