The Context Window Is a Desk, Not a Memory

Most developers treat the context window like a database. It is not. It is a working desk. Whatever is on the desk when your agent starts a task is the totality of what it knows for that task. Previous runs, learned behaviors, prior decisions - none of that exists unless you deliberately put it on the desk before the agent starts. This distinction changes how you debug agents. The wrong mental model When an agent does something unexpected, the reflex is to blame the model: "Claude hallucinated," or "the LLM made something up." Sometimes that is true.