Inspired by `robots.txt`, the `llms.txt` standard proposes a single Markdown document at the root of a site that lists the most important URLs and their summaries — designed for LLM (Claude, Perplexity, ChatGPT) consumption when crawling for citation. AI2 Design ships both `/llms.txt` (index, 100 lines) and `/llms-full.txt` (deep, full content) — the latter includes complete curator verdicts and 24-field brief bundles (18-field agent brief + 6-field curator).
Glossary · ai agents
llms.txt
A proposed standard text file at /llms.txt that exposes a site's primary content in a format optimized for LLM ingestion.
External reference
llms.txt — Proposed Standard