Guides · HolicAudit

What is llms.txt, and how do you write one?

Published 2 November 2026

In short: llms.txt is a Markdown file at /llms.txt that gives AI tools a short summary of your site and links to your most useful pages. It's a proposed convention, not an official web standard, and the big AI search engines haven't said they use it. It takes ten minutes to write, so it's a reasonable extra, not a fix.

Where it comes from

Jeremy Howard of Answer.AI proposed llms.txt in September 2024 at llmstxt.org. The idea: web pages are full of navigation, scripts and layout, and language models have limited context, so a site can offer a clean, curated Markdown index for them. Many documentation platforms now generate one automatically.

Who actually reads it

Be realistic. Google representatives have said Google Search doesn't use llms.txt, and OpenAI, Anthropic and Perplexity haven't announced that their search crawlers rely on it. Where it does get used today is by developers and AI coding tools: people paste a docs site's llms.txt into ChatGPT, Claude or Cursor to give the model accurate context, and some agents look for it. So it matters most for documentation, APIs and developer products.

The format

The proposal defines a simple structure, in this order:

An H1 with the name of the site or project. This is the only required part.
A blockquote with a one or two sentence summary.
Optional paragraphs or lists with more detail (no headings).
H2 sections, each with a list of links: - [Title](https://url): optional note.
An optional section titled ## Optional for links an AI can skip when it's short on context.

Example

# Acme Invoicing

> Acme is invoicing software for freelance designers in the EU. Plans from EUR 9/month, VAT-compliant invoices, free 14-day trial.

Acme sends invoices, tracks payments and files VAT reports. It does not do payroll.

## Product
- [Features](https://acme.example/features): what Acme does, with screenshots described in text
- [Pricing](https://acme.example/pricing): plans, limits and what's included
- [Security](https://acme.example/security): data storage, encryption, GDPR

## Docs
- [Getting started](https://acme.example/docs/start.md): create your first invoice
- [API reference](https://acme.example/docs/api.md): REST endpoints and auth

## Optional
- [Changelog](https://acme.example/changelog)
- [Blog](https://acme.example/blog)

Writing a good one

Write the summary as the answer you'd want an AI to give about you: what it is, who it's for, the price range.
Link your money pages and docs, not every URL. That's what the sitemap is for.
Use absolute URLs and keep notes factual. Don't stuff keywords: it's read by models, not ranked.
The proposal also suggests offering Markdown versions of pages at the same URL plus .md. Nice for docs, optional for everyone else.
Serve it as plain text or Markdown with a 200 status. A common bug: single-page apps answer /llms.txt with their HTML shell.

llms-full.txt

Some sites, mostly documentation, also publish /llms-full.txt: the full text of all their docs in one Markdown file, so a tool can load everything at once. It isn't in the original proposal but has become a common companion. Skip it unless you have docs people use with AI tools.

Check yours

Our AI visibility check fetches your /llms.txt and /llms-full.txt, checks the H1, summary and links, and also checks the things that matter more: AI crawler rules in robots.txt and whether your pages have readable text before JavaScript runs.

Frequently asked questions

Is llms.txt an official standard?

No. It's a community proposal from September 2024 published at llmstxt.org. No standards body has adopted it and major AI search engines haven't committed to using it.

Will llms.txt improve my rankings or get me cited?

There's no evidence it does. Google has said Search doesn't use it. Treat it as a cheap convenience for AI tools and developers, not an SEO tactic.

Is llms.txt the same as robots.txt?

No. robots.txt tells crawlers what they may fetch. llms.txt is a reading list that points AI tools to useful pages. It doesn't allow or block anything.

Where do I put it?

At the root of your domain, for example https://example.com/llms.txt, served as text/plain or text/markdown.