What Is llms.txt and How to Set It Up (2026 Guide)

If you have never heard of llms.txt, you are not alone. It is a fairly new file format, and most sites still don't have one. That is actually good news for you, because setting it up now puts you ahead of most competitors in your niche.

What is llms.txt?

llms.txt is a plain markdown file placed at the root of your domain, at yourdomain.com/llms.txt. It gives AI systems a short, structured summary of what your site offers and which pages matter most. Think of it as a clean index card for AI tools, instead of them having to guess your site structure from scratch.

Why it matters

• It helps compatible AI systems understand your site faster and more accurately
• It gives you a chance to describe your product or content in your own words, not an AI's guess
• It costs nothing to set up and takes about 15 minutes
• Almost nobody has one yet, so it is an easy way to stand out

How to write one

Keep it short and in plain markdown. Start with your site name and a one-line description, then list your key pages with a short summary for each.

# Your Site Name

> One-line description of what your site or product does.

## Key Pages

- [Home](https://yoursite.com): What visitors find here
- [Docs](https://yoursite.com/docs): Product documentation
- [Pricing](https://yoursite.com/pricing): Plans and pricing details
- [Blog](https://yoursite.com/blog): Articles and guides

Where to put it

Upload the file to the root of your domain so it's reachable at yoursite.com/llms.txt, exactly like robots.txt or sitemap.xml. On most platforms this means placing it in your public or static folder. Test it by visiting the URL directly in your browser after publishing.

Keep it updated

Update your llms.txt whenever you add an important new page, like a major product feature or a cornerstone blog post. A stale llms.txt is better than none, but a current one works harder for you.

This is one part of a bigger process. The AI SEO Mastery Notion template covers llms.txt, llms-full.txt, robots.txt rules for AI crawlers, and 9 more sections, with 40+ ready-to-use prompts included.