Why have an MCP server instead of a simple instructions file?It seems lighter weight, similar to existing paradigms, and ultimately if you re pointing at another place anyway - why not just have a declarative file that very thinly instructs what to do and provides endpoints?Imagine every server with an agents.txt. It s backwards compatible. Anyone today from PHP to Node or whatever, on Heroku, S3, anywhere - you can add a agents.txt and tell LLMs what to do with your site.I can imagine that it could be extended with credentials and so forth.Why do I need MCP, or what does it bring that I can t accomplish with a static file?