We’re in the middle of the biggest shift in how we build software. Traditionally, software is very deterministic: whatever pre-defined instructions you write, your software behaves exactly like that. With deterministic software, it’s pretty intuitive to secure it, because you mostly know the points of failure and you secure them.

But this shift has been tremendous with the coming of agentic AI that uses large language models. The old rules still apply, but they’re not enough anymore, and figuring out why they’re not enough and how you can fix it is basically what this blog is about.

This is my first post in my “Today I Learned” series. Words like MCP host, MCP server, protocol, agent, subagent, tool, and RAG get thrown around so easily as buzzwords. I tried to put together a simple explanation of them so that anyone can understand it.