llms.txt is the New robots.txt for AI Engines: Complete Implementation Guide
llms.txt is the standard that tells AI engines what your website is about, what content is available, and where to find it. Wikipedia updated its SEO article on April 19, 2026 to include generative engine optimization (GEO) as the prevailing term for LLM-based search optimization. Yet 95% of websites still do not have an llms.txt file. This is the robots.txt moment for AI discovery. The brands that implement llms.txt now will control how AI engines like ChatGPT, Perplexity, and Gemini understand and cite their content. The brands that wait will be invisible. ...