Agentic

Warning

llms.txt file is missing

This notice appears when your domain doesn't serve a reachable llms.txt file. Here's what it is, what it's for, and how to publish one if it's worth it for you.

What this error means

llms.txt is an emerging standard, not yet mandatory or universally adopted, meant to let AI agents quickly understand what your site is about without crawling every page's full HTML. The file is published as plain text at the root of the domain (https://yourdomain.com/llms.txt) and follows a Markdown format: a main title, optionally a short summary, and sections with links to the site's most relevant pages. We checked and your domain doesn't serve this file: the request to that URL returns a 404. Technically this is the same as not declaring anything, much like a missing robots.txt. Not having llms.txt isn't an error in the classic SEO sense: it's an improvement opportunity specifically aimed at how AI assistants read your site, not at how you rank in traditional search engines.

Why it matters to fix it

This notice doesn't hurt your classic SEO ranking, but it does have concrete consequences for how AI agents find and interpret you.

Slower understanding by AI agents

Without llms.txt, an agent has to crawl and parse your entire HTML to figure out what your site is about, instead of starting from a ready-made summary.

Lower odds of being cited in answers

Assistants that do use this file may favor sites that publish it when deciding which sources to cite.

A missed chance to control the narrative

Without this file, you lose the chance to decide yourself which pages to highlight as most relevant to an AI agent, instead of leaving it to infer on its own.

No effect on your traditional SEO

Search engines like Google don't rely on llms.txt at all: this is a signal specific to the AI agent ecosystem, and it doesn't replace or compete with your sitemap or robots.txt.

How to fix it step by step

Publishing an llms.txt is straightforward once you know which pages you want to highlight.

Step 1

Pick your site's most important pages

Think of the 5-10 URLs that best represent what you do, who you serve, and how to reach you.

Where to apply it: Homepage, main product/service pages, about, contact.

Step 2

Write the title and summary

Start the file with an H1 title (a hash, a space, and your site's name) and, optionally, a short blockquote summarizing what you do.

Where to apply it: First line of the llms.txt file.

Step 3

Add sections with links

Organize the rest of the content into H2 sections with markdown lists of links to your key pages.

Where to apply it: Body of the file, following the llmstxt.org specification.

Step 4

Publish it at your domain's root

Upload the file so it responds at https://yourdomain.com/llms.txt with a 200 status and plain text content type.

Where to apply it: Your server or CMS, at the domain root.

If you want to understand it even better

To help you better understand this type of error and why it happens, we include additional materials that expand the explanations, guide with examples, or show alternative methods.

llmstxt.org

Official specification for the llms.txt format.

View resource

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