llms.txt spec adds link relations for Markdown discovery
Jeremy Howard, the Answer.AI developer who created llms.txt, published a version 2 update to the spec on August 10 — its first revision since the format launched in 2024. The update adds rel="alternate" type="text/markdown" and rel="describedby" link relations so AI agents and coding tools can find a page’s Markdown version and the llms.txt file that covers it, per Search Engine Journal and the spec’s changelog at llmstxt.org. Existing implementations need only minor changes, since the original URL pattern still works.
Why it matters: It's the first revision to the category's most-discussed AI-agent text file since it launched in 2024, formalizing machine discovery even as Google says Search itself ignores the file.
The record: llms.txt
Glossary: llms.txt
Posted to the wire August 17, 2026.