llms.txt Validator

Check any domain's llms.txt against the real spec, missing title, broken links, relative URLs, and the other mistakes that stop an AI assistant using it properly.

Website domain *

What this checks

A single H1 title, first in the file: The spec requires the very first line to be `# Your Site Name`. Content or extra H1s before it are flagged.

A summary blockquote right after the title: Not required, but it's the first thing AI tools read about your site: a `>` line straight after the H1.

Well-formed links in every section: Each H2 section should hold a markdown list of `[title](url): notes`. Broken syntax, missing URLs, and empty sections are flagged.

Absolute URLs, no duplicates: Relative paths force an AI tool to already know your domain to resolve them; repeated URLs are usually a copy-paste mistake.

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