Check compliance with the llms.txt specification. Catch errors, verify structure, and ensure your site is ready for AI agents and language models.
Detect llms.txt ↓Enter a URL and we'll check the root for llms.txt, llms-ctx.txt, and llms-full.txt.
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Reading the site and generating llms.txt with Claude Haiku... this can take 10–20 seconds.
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The llms.txt specification is a proposed standard that helps websites provide structured, LLM-friendly content. Think of it as a robots.txt for AI — a simple markdown file that tells language models what your site is about and where to find key resources.
The format supports three file types: llms.txt for a concise overview, llms-ctx.txt for additional context, and llms-full.txt for comprehensive documentation. Each follows a clean markdown structure with headers, descriptions, and categorized links.
As AI agents become more prevalent, having a well-structured llms.txt file ensures your content is discoverable, accessible, and correctly interpreted by language models.
Detect missing headers, malformed links, encoding issues, and structural problems before they reach production. Line-by-line feedback shows you exactly what to fix.
Validate against the official llms.txt specification. Check required fields, recommended sections, link formats, and file size limits automatically.
A valid, well-structured llms.txt makes your site more accessible to AI crawlers and language models, ensuring your content is properly indexed and understood.
Validate any live site by entering its URL. Handles redirects, encoding detection, and TLS-protected sites.
Validate llms.txt, llms-ctx.txt, and llms-full.txt files with format-specific rules and size limits.
Automatic character encoding analysis with BOM detection, UTF-8 validation, and server header comparison.
Visual breakdown of your file structure: H1 titles, blockquotes, H2 sections, and link inventory.
Approximate LLM token counts so you can gauge context window usage before feeding content to a model.
Fix issues directly in the browser, then download the corrected file as clean UTF-8 text.
Enter a URL, paste content directly, or upload a .txt/.md file from your computer.
We check structure, links, encoding, and compliance against the llms.txt specification.
Get line-by-line feedback, fix issues inline, and download the corrected file.
Check your llms.txt file in seconds. Free, instant, no sign-up required.
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