llms.txt Check

llms.txt is a plain-text file at the root of your domain that gives AI engines a concise, structured summary of your site — what it is, your key pages, and how to describe you. Think of it as robots.txt for large language models. VitalSite's AI Visibility checks whether you publish one and whether it is useful.

What VitalSite checks

• Presence. Whether https://yourdomain.com/llms.txt exists and returns plain text.
• Usefulness. Whether it actually summarizes your site and links your most important pages, rather than being empty or boilerplate.

Why it matters

AI engines have a limited budget for reading any single site. An llms.txt hands them a clean, authoritative summary instead of forcing them to infer everything from your HTML — which makes it far more likely they describe and cite you correctly. It is one of the newest but highest-leverage AI-visibility signals.

How to fix it

Create a file named llms.txt in your site root (the same place as robots.txt). A simple, effective structure:

# Your Company
> One-sentence description of what you do.

## Key pages
- [Product](https://yourdomain.com/product): what it is
- [Pricing](https://yourdomain.com/pricing): plans and prices

## Contact
- hello@yourdomain.com

Keep it in plain language, lead with a direct description, and link the pages you most want cited.

Verify the fix

Re-scan your domain. The LLM-optimization category in AI Visibility should recognize the file and reflect it in your score.

Run a free full-domain scan to see whether this affects your site — every page, with an exact fix guide. Pro and Agency plans add PDF export and monitoring.