# llms.txt existence

> llms.txt is a Markdown file at the root of a website that gives AI models a short overview of the site and links to its most important pages.

- **Check ID:** A6
- **Area:** [AI Readiness](https://be1st.ai/glossary/ai-readiness)
- **Tool:** [AI Readiness](https://be1st.ai/tools/ai-readiness)
- **Page:** https://be1st.ai/glossary/ai-readiness/llms-txt-existence

## Why it matters

The llms.txt file is designed specifically for LLM models to quickly understand a website's purpose, services, and structure. Unlike robots.txt which controls access, llms.txt actively helps AI understand your content. Its mere existence is a strong signal that the site is AI-ready.

## In practice

Stripe has one of the best llms.txt files: it contains a product overview, links to documentation, and API references. Thanks to this, ChatGPT and Claude can accurately answer questions about Stripe products.

## How be1st checks it

Checks for the existence of the /llms.txt file: a new standard that provides AI models with a structured overview of a website in Markdown format. Only the presence of the file is evaluated: content quality is assessed in a separate check A7.

[AI Readiness](https://be1st.ai/tools/ai-readiness), Content tab.

Every check ends as: Pass, Warning, Fail.

## Sources

- [The /llms.txt File Specification](https://llmstxt.org/) (llmstxt.org)
- [OpenAI llms.txt Documentation](https://developers.openai.com/api/docs/llms.txt) (OpenAI)

## Related terms

- [robots.txt](https://be1st.ai/glossary/seo/robots-txt): robots.txt is a plain text file at the root of a website that tells crawlers which parts of the site they may and may not visit.
- [llms.txt content quality](https://be1st.ai/glossary/ai-readiness/llms-txt-content-quality): llms.txt content quality is how useful that file is to an AI model: a clear description of the site, working links to its sections and enough detail.
- [llms-full.txt](https://be1st.ai/glossary/ai-readiness/llms-full-txt): llms-full.txt is an extended version of llms.txt that holds the full text of a website's key documentation in one Markdown file.
- [BLUF (bottom line up front)](https://be1st.ai/glossary/ai-readiness/bluf-bottom-line-up-front): BLUF (Bottom Line Up Front) is a writing principle: put the answer or the key point first and add the details after it.
- [Content structure (lists, tables)](https://be1st.ai/glossary/ai-readiness/content-structure): Content structure is how a page organizes information into lists, tables and other formats that readers and AI models can scan quickly.
- [FAQ section on page](https://be1st.ai/glossary/ai-readiness/faq-section-on-page): An FAQ section is a visible block of questions and answers in the content of a page, as opposed to FAQ markup hidden in the code.