What is llms.txt and do I need one?

llms.txt is a plain-text file at your domain root that gives AI crawlers a curated map of your site — what it is, what's important, where the canonical pages live. Think robots.txt, but for helping LLMs understand rather than restricting them. It takes minutes to generate and costs nothing, so yes: if any of your traffic strategy involves AI search (and in 2026 it should), ship one. It's not a magic ranking lever, but it removes friction from being understood and cited correctly.