Free tool

Generate and validate llms.txt

Enter a website: we check whether it has an llms.txt that follows the llmstxt.org format and build a draft from the site navigation. Edit the draft and upload it to the site root.

Free, no sign-up. We read /llms.txt at the site root and the homepage, which takes up to 15 seconds.

What it is

What is llms.txt

llms.txt is a Markdown file at the site root that tells language models and AI agents what the site is and which pages matter most. Unlike sitemap.xml, it is not a full list of URLs but a short table of contents with notes.

The format was proposed in 2024. It helps AI assistants and agents find the right pages right away instead of parsing layout, menus and scripts.

File format

# Company name

> One or two sentences on what the company does and for whom.

## Main pages

- [Catalog](https://example.com/catalog): models and prices
- [Delivery](https://example.com/delivery): timing and regions
- [Contacts](https://example.com/contacts): address and phone

## Optional

- [Blog](https://example.com/blog)

Only the H1 title is required. A > summary and ## sections with links are the recommended structure. An agent may skip the Optional section when context is short.

What we check

Six checks against the llmstxt.org format

01

File at the site root

Whether /llms.txt opens, which status code the server returns and where redirects lead.

02

Content type

Whether the file is served as text/plain: with text/html it is easy to mistake for a web page.

03

Structure

An H1 title at the top, a short > summary and ## sections.

04

Links

The [Title](URL) item format, full https:// URLs and repeated pages.

05

Fallback page instead of the file

Whether the site answers /llms.txt with the homepage, as SPAs and some CMSs do.

06

llms-full.txt

Whether an extended file with the full text of key pages exists. It is optional but useful for documentation.

How to publish

How to put llms.txt on your site

  1. 01

    Save the file

    UTF-8 encoding, the name llms.txt, Markdown format. The draft above downloads with one click.

  2. 02

    Upload it to the site root

    Into the public or static folder of the project or through the CMS file manager, so it opens at your-site.com/llms.txt.

  3. 03

    Check how it is served

    The server should return 200 with text/plain; charset=utf-8 and no redirect to the homepage.

  4. 04

    Add descriptions

    After a colon, add one sentence about what is on each key page.

  5. 05

    Check again

    Run the check again and update the file whenever the site structure changes.

FAQ

llms.txt questions

What is llms.txt?
A Markdown text file at the site root that describes the site for language models: its name, a short summary and a list of key pages with notes. Jeremy Howard of Answer.AI proposed the format in 2024. More in the llms.txt guide.
Does llms.txt affect visibility in ChatGPT, Perplexity and other AI engines?
There is no direct confirmation yet that major AI search engines use llms.txt when choosing sources. AI agents and developer tools do read it, and it is a cheap way to give them an accurate map of key pages. Citations in answers depend more on content and external brand mentions, which monitoring can measure.
Where should the file go?
At the domain root so it opens at your-site.com/llms.txt. The server should return it with status 200 and text/plain; charset=utf-8. Each subdomain needs its own file.
How is llms.txt different from robots.txt and sitemap.xml?
robots.txt controls bot access to pages, sitemap.xml lists every URL for search crawlers, and llms.txt is a short curated map of what matters most, with plain-language notes for language models.
Should llms.txt be listed in robots.txt?
No, the format does not require it: agents look for the file at the fixed /llms.txt path. What matters is not blocking the file or AI bots in robots.txt.
What is llms-full.txt?
A common extension of the format: a single file with the full text of key pages such as documentation or a knowledge base. llms.txt stays a short table of contents.
Is it free? Are there limits?
Yes, free and without sign-up. Up to 10 checks per 10 minutes from one address. The draft is built from the homepage navigation, so edit it before publishing.