How to validate your llms.txt
Seven short steps, in order. Most problems are on the first line or in the links.
Check your llms.txt now
Free, no sign-up. We read your /llms.txt the way an assistant would, and show each problem with its line and the fix.
Check your whole site: what an assistant can do with your business, and what's missing.
Seven steps
- Open it
Open yoursite.com/llms.txt in a browser. You should see plain text, not your homepage or an error page. - Check line 1
Line 1 is your name after one #:# Your Business. It's the one line the format requires. - Add a summary
Below it, one line that starts with >: what you do, and where. Optional, but readers like it. - Make every link a link
Under each ## heading, one link per line:- [Name](https://…): a short note. Use full https addresses. - Run a validator
Put your website into the llms.txt checker at the top of this page, and fix each line it names. - See what Lighthouse says
Optional: in Chrome, open DevTools, then Lighthouse, tick the Agentic Browsing category and run it. - Check again
Upload the fixed file, then check again. A cache may show the old file for a little while.
Common errors and how to fix them
| What you see | The fix |
|---|---|
| Your homepage, or a “page not found” page, at /llms.txt | There's no file yet. Upload a file named llms.txt to your site's root, or turn it on in your platform. |
Line 1 isn't # Your name | Make line 1 your business's name after one # and a space. Nothing but blank lines may come before it. |
- Menu: https://… | Write it as a link: - [Menu](https://…): lunch and dinner. Chrome's Lighthouse fails a file with no Markdown link. |
### headings, or a heading between your name and your sections | Keep one # line for your name, and use ## for every section. |
http:// or /menu | Use the full address with https: https://yourbusiness.com/menu. |
| A link leads to a missing page | Fix the address, or remove the line. |
| Your robots.txt blocks /llms.txt | Allow it: readers that obey robots.txt won't fetch a blocked file. The AI crawler checker shows the line. |
| Error 403 or 429, or a “checking your browser” page | Your host or firewall stops readers. Ask it to let /llms.txt through. |
| Odd characters, such as é instead of é | Save the file as UTF-8 plain text. |
What a valid file looks like
Short, with your name first and one link per line:
# Crumb & Co. Bakery
> Bakery and café for sourdough, pastries and celebration cakes. Open every day from 7:00.
## Visit and order
- [Menu and prices](https://crumbandco.example/menu): breads, pastries and coffee
- [Order a cake](https://crumbandco.example/cakes): three days' notice
- [Opening hours and how to find us](https://crumbandco.example/visit)
## Optional
- [Our story](https://crumbandco.example/about)More examples: a restaurant, a salon, a clinic, a shop, a trade and more.
What a valid file does, and doesn't
Google Search doesn't use llms.txt. Chrome's Lighthouse audits it, and some AI tools read it.
A valid file helps an assistant read about you. To let it ask, book or order, you need a door: a tool, an API or an agent inbox that takes the request. More in what llms.txt does, and doesn't.
Questions
What makes an llms.txt valid?
Per llmstxt.org, only one thing is required: a # heading with your name. A good file adds a > summary and ## sections of [name](url) links.
Does Google check my llms.txt?
Google Search doesn't use it. Chrome's Lighthouse (13.3 and later) audits it under Agentic Browsing: a # heading, at least 50 characters and one Markdown link.
Is llms-full.txt required?
No. llms-full.txt is a community convention, not part of the llms.txt proposal.
Can my llms.txt live in a folder?
Yes. Since version 2 of the proposal (August 2026), a file at a path such as /docs/llms.txt covers the pages under that path.