Free Chrome extension AI SEO & GEO Readiness Checker Check llms.txt alongside crawler access, schema, sitemaps, and page structure. View extension Experimental file-format check

Check your llms.txt file structure — 2-UA

Validate reachability, Markdown structure, section links, robots compatibility and the llms-full.txt companion. This cannot predict AI visibility.

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Validate your file

Check whether your site publishes a reachable, well-formed /llms.txt file. The check covers structure, blockquote summary, H2 sections, link quality, /llms-full.txt companion and robots.txt compatibility. The format is experimental; passing does not guarantee crawling, indexing, citations, rankings, or AI visibility.

Enter any domain — we probe /llms.txt at its root. Don't have one yet? Generate one from your sitemap →

What is llms.txt?

llms.txt is a proposed standard by Jeremy Howard (Answer.AI) — a plain-text markdown file published at the root of a domain (https://example.com/llms.txt). It is intended to describe a site and point to selected pages for tools that choose to read it. Unlike robots.txt, it does not control crawler access, and adoption varies.

What this validator checks

Reachable at /llms.txt

The file is served at the canonical path with HTTP 200 and text/plain or text/markdown.

Single H1 title

The first line must be # Your project name — exactly one H1.

Blockquote summary

One-line > short summary right after the title describes the file scope.

H2 sections with links

Groups of ## Section name each containing - [Title](url): description bullets.

Link quality audit

Every bullet has a human-readable title, an absolute URL, and an optional description.

Companions & robots

Checks for optional /llms-full.txt and ensures robots.txt doesn't block the file.

Minimal llms.txt example

# FastHTML

> The fastest way to build modern Python web apps.

FastHTML is a Python framework for building server-rendered web apps with minimal boilerplate.

## Docs

- [Quick start](https://fastht.ml/docs/start.md): 5-minute intro
- [API reference](https://fastht.ml/docs/api.md): All classes and functions
- [Deployment guide](https://fastht.ml/docs/deploy.md): Production recipes

## Examples

- [Todo app](https://fastht.ml/examples/todo.md)
- [Chat app](https://fastht.ml/examples/chat.md): Real-time with websockets

## Optional

- [Changelog](https://fastht.ml/changelog.md)
- [Contributing](https://fastht.ml/contributing.md)

What an llms.txt can and cannot do

Optional content map

The proposed format gives tools that choose to read it a curated list of pages. Adoption varies, and publishing the file does not cause or guarantee crawling, citations, rankings, traffic, or AI visibility.

Context-window friendly

Full HTML pages with nav, ads and scripts waste LLM context. llms.txt points to .md or clean pages — a companion /llms-full.txt can even deliver the entire corpus in a single request for RAG pipelines.

Spec status (April 2026): llms.txt is a community standard maintained at llmstxt.org. It is not a W3C standard, and support varies between tools. Treat validation as file-format evidence, not evidence of search or answer-engine visibility.