agents.json Explained: How to Make Your Website Machine-Readable

Every era of the web has gotten its discovery files. Files that sit in the background telling machines: "Here I am, this is what I can do." Most website operators know at least two of them. But very few know that a third one is emerging -- and that it might become the most important. The Evolution of Discovery Files 1994: robots.txt -- Tell the Crawlers What They May Do User - agent : * Disallow : / admin / Allow : / Simple. Effective. robots.txt tells search engine crawlers which parts of a website they may index and which they shouldn't. No webmaster in 1994 thought this text file would ever become critical. Today, every serious website has one. 2005: sitemap.xml -- Show the Crawlers What Exists <urlset xmlns= "http://www.sitemaps.org/schemas/sitemap/0.9" > <url> <loc> https://example.com/ </loc> <lastmod> 2026-02-15 </lastmod> <priority> 1.0 </priority> </url> </urlset> robots.txt says what crawlers shouldn't touch. sitemap.xml says what they should find. Together, they form the fou