In 2026, what I'm about to describe would be a three-tool agent loop. An LLM instance with computer use, a couple of MCP servers, maybe a router for the edge cases. A weekend project. When I actually built it, none of that existed. What I had was Puppeteer, three vastly different internal systems with no usable APIs, and a two-month backlog of customer escalations my team couldn't clear because each ticket required logging into all three systems, correlating what you found, and making a judgment call. We were a team of five. The backlog was hundreds deep and growing. I cleared it in a week. This isn't a post about how clever the script was; it wasn't, particularly. It's a post about what I learned doing the work of an AI agent by hand, before the agents showed up in droves. Because looking back, the code was the easy part. The hard part was the same part agents are still tripping over today: knowing which discrepancy means something and which one is just a guy on a business trip.…