Does your website have a working llms.txt file?
Check whether your site has an llms.txt file and whether it follows the proposed format. Free, no sign-up.
What is llms.txt?
llms.txt is a proposal, published at llmstxt.org, for a short plain-text file at the root of a website, for example example.com/llms.txt. It is written in Markdown and gives AI tools a quick guide to your site: what it is, and which pages matter most. Think of it as a hand-written table of contents for machines.
It has a simple shape: a title, a short summary, and sections of links.
# Your Business Name > One or two sentences on what you do and who you do it for. ## Main pages - [Services](https://example.com/services): what you offer - [About](https://example.com/about): who you are - [Contact](https://example.com/contact): how to reach you ## Optional - [Blog](https://example.com/blog): articles and guides
What this checker looks at
- Whether a file answers at /llms.txt, and whether it is plain text rather than a web page.
- Whether it starts with a title, has a short summary, and groups links under headings.
- Whether the links are full https:// addresses, and whether the file is a sensible size.
- Whether an optional llms-full.txt exists, and whether your robots.txt lets tools read the file.
It reads only your robots.txt, llms.txt and llms-full.txt files, and it does not visit the pages the file links to.
Do you need one?
Not necessarily. The file is optional, adoption is uneven, and there is no confirmed evidence that having one improves your rankings or how often AI tools mention you. Large search engines have said they do not rely on it. Adding one costs very little, and a clear summary of your site is useful either way, but fix the basics first: a site that crawlers can read, clear page titles, and content that answers real questions.
Common mistakes
- A custom “page not found” page answers at /llms.txt, so the site looks like it has the file but does not.
- No title on the first line, or a title that is not a heading.
- Relative links such as /services instead of full https:// addresses.
- Pasting the whole site into one huge file instead of a short guide.
- A robots.txt rule that blocks the file.
Questions people ask
Do ChatGPT and Claude read llms.txt?
Support varies by tool and changes over time. Some tools and developer products read it. Check the documentation of the tools you care about instead of assuming.
Where do I put the file?
At the root of your domain, so it opens at yourdomain.com/llms.txt. A file in a subfolder is not found.
What is llms-full.txt?
An optional longer companion with your full content in one file. You can skip it.
Check the rest of your AI readiness
See which AI crawlers your robots.txt allows, or run the free audit for titles, headings, links and structured data across your pages.