---
title: "llms.txt"
description: "Automatically generate llms.txt and llms-full.txt files so AI tools like ChatGPT and Claude can index and understand your documentation."
keywords: ["llms.txt", "LLM indexing", "AEO", "GEO", "content discovery"]
boost: 3
---
import { PreviewButton } from "/snippets/previewbutton.jsx"
The [llms.txt file](https://llmstxt.org) is an industry standard that helps large language models (LLMs) index content more efficiently, similar to how a sitemap helps search engines. AI tools can use this file to understand your documentation structure and find content relevant to user queries.
Mintlify automatically hosts an `llms.txt` file at the root of your project that lists all available pages in your documentation. This file is always up to date and requires zero maintenance. You can optionally add a custom `llms.txt` file to the root of your project.
Authentication affects `llms.txt` and `llms-full.txt` differently depending on your site configuration:
- **Fully authenticated sites**: Both files require authentication. AI tools that cannot authenticate cannot access them.
- **Partially authenticated sites**: Both files are publicly accessible, but only list public pages and exclude pages restricted to user groups.
For more information on how authentication affects AI features, see [Feature availability](/deploy/authentication-setup#feature-availability).
View your `llms.txt` by appending `/llms.txt` to your documentation site's URL. Mintlify also hosts the file at `/.well-known/llms.txt` for compatibility with tools that follow the `.well-known` convention.
Open the llms.txt for this site.
Mintlify adds HTTP headers to every page response so AI tools can discover your `llms.txt` files and other agent resources without prior knowledge of their location:
- `Link`: Follows the standard HTTP `Link` header format for resource discovery. Advertises `llms.txt`, `llms-full.txt`, your API catalog, [MCP server card](/ai/model-context-protocol#discovery-endpoint), [agent card](/ai/skillmd#agent-card), and [agent skills index](/ai/skillmd#skills-discovery-endpoints).
- `X-Llms-Txt`: A convenience header for tools that check for `llms.txt` support.
```http Response headers
Link: ; rel="llms-txt", ; rel="llms-full-txt", ; rel="api-catalog", ; rel="mcp-server-card", ; rel="agent-card", ; rel="agent-skills"
X-Llms-Txt: /llms.txt
```
Sites that use authentication also advertise their OAuth protected resource metadata with `rel="oauth-protected-resource"`. If you serve your documentation under a base path, every advertised path includes that prefix.
## Structure of the llms.txt file
An `llms.txt` file is a plain Markdown file that contains:
- **Site title** as an H1 heading.
- **Site description** as a blockquote summary below the title, sourced from the `description` field in your `docs.json` configuration.
- **Custom agent instructions** as an `Agent Instructions` block after the description, if you set [`markdown.instructions`](/ai/markdown-export#custom-agent-instructions) in your `docs.json`.
- **Structured content sections** with links and a description of each page in your documentation.
- **API specification links** to your OpenAPI and AsyncAPI specs, if your documentation includes them.
- **External links** in an `Optional` section, for any absolute URLs in your navigation.
The `llms.txt` file lists your pages in the order they appear in your `docs.json` navigation. Pages that aren't in your navigation but that `seo.indexing: "all"` includes appear last, in alphabetical order. Page links in the `llms.txt` file include a `.md` extension so AI tools can fetch the Markdown version of each page directly.
Each page's description comes from the `description` field in its frontmatter. Mintlify uses the first paragraph of the description and truncates it at 300 characters. Pages without a `description` field appear in the `llms.txt` file without a description.
Both `llms.txt` and `llms-full.txt` list pages from your default language and default version. They exclude [hidden pages](/organize/hidden-pages) and pages with `noindex: true` in their frontmatter unless you set `seo.indexing: "all"` in your `docs.json`.
This structured approach allows LLMs to efficiently process your documentation at a high level and locate relevant content for user queries, improving the accuracy and speed of AI-assisted documentation searches.
Automatically generated `llms.txt` files cannot exceed 100,000 characters. As a file approaches this limit, Mintlify shortens page descriptions first, then drops entries and appends a note listing what it omitted. This limit does not apply to `llms-full.txt`. To list every page without truncation, add a [custom `llms.txt` file](#custom-files) at the root of your project.
```mdx Example llms.txt
# Site title
> A brief description of the documentation site.
## Docs
- [API](https://example.com/docs/api.md): Endpoint list and usage
- [Install](https://example.com/docs/install.md): Setup steps
- [Getting started](https://example.com/docs/start.md): Intro guide
## OpenAPI Specs
- [openapi](https://example.com/docs/openapi.json)
## AsyncAPI Specs
- [asyncapi](https://example.com/docs/asyncapi.yaml)
## Optional
- [Community](https://example.com/community)
```
## llms-full.txt
The `llms-full.txt` file combines your entire documentation site into a single file as context for AI tools and LLM indexing. Each page appears as its title, source URL, description, and full Markdown content.
Mintlify automatically hosts an `llms-full.txt` file at the root of your project. View your `llms-full.txt` by appending `/llms-full.txt` to your documentation site's URL. Mintlify also hosts the file at `/.well-known/llms-full.txt` for compatibility with tools that follow the `.well-known` convention.
Open the llms-full.txt for this site.
## Custom files
To add a custom `llms.txt` or `llms-full.txt` file, create an `llms.txt` or `llms-full.txt` file at the root of your project. Adding a custom file overrides the automatically generated file of the same name. If you delete a custom file, Mintlify restores the automatically generated file.
Your custom `llms.txt` or `llms-full.txt` file must have a site title as an H1 heading. Other content is optional. See [Format](https://llmstxt.org/#format) in the `llms.txt` specification for more information on optional sections and best practices.