llms.txt checker: is your llms.txt valid?

Check a live site

Or paste the file

What makes an llms.txt valid

The llmstxt.org proposal has exactly one required part: a first line # Your site name. Everything else is optional, so this checker never fails a file for missing it:

• a > summary line: one sentence about the site;
• free text with more detail;
• ## Section headings with markdown link lists, - [Title](https://...): note;
• a ## Optional section for pages an agent may skip when it is short of room.

The file fails when it is not there (any status but 200), is empty, starts with something other than the # title, or is an HTML page. That last one is the failure we see most: many site builders answer every unknown address with the home page and status 200, so /llms.txt "exists" but is a web page.

llms.txt is a hint for agents, not a search ranking factor. It helps most for sites whose useful pages are hard to find from the home page: docs, shops, tools.

A valid example

The Try the example button checks this file:

# Example Bakery

> Small-batch bakery in one town: order cakes online for pickup, see prices and opening hours.

## Shop
- [Cakes and prices](https://example.com/cakes/): every cake with its price and lead time
- [Order for pickup](https://example.com/order/): order form, no account needed

## Help
- [Opening hours and address](https://example.com/visit/)
- [Allergens](https://example.com/allergens/): what is in each cake

## Optional
- [Our story](https://example.com/about/)

Serve it as plain text at https://yoursite.com/llms.txt. On Shopify, Squarespace or Wix you may not be able to add a root file; the full check below says what your platform allows.

Check the rest of what an agent meets

An llms.txt is one of about a dozen things. The free Agent-Ready Check also reads your robots.txt rules for 12 AI bots, looks for captchas and bot walls on sign-up and contact pages, text that only appears after JavaScript, JSON-LD and prices, and MCP/agent cards. See also the robots.txt AI bot checker.