The first sign something was wrong was the invoice.

Not catastrophically wrong. More like “this escalated quietly while I was having fun” wrong. I’d been using Claude Code the way most people start: throw everything at it, stay in the session, keep talking. It felt productive. It was productive. And it was also quietly burning through tokens at a rate I hadn’t tracked because tracking it felt like it would interrupt the flow.

The flow, it turned out, was expensive.

The Context Window Is Not Your Notebook

The first thing I fixed was the worst habit I’d developed without noticing: treating a session like a shared workspace that persisted naturally.