The context window is the onboarding period. Every invocation is a new hire reading the codebase for the first time.

This is why architecture legibility keeps getting more important. Clean interfaces, small modules, good naming. Not because the human needs it (they already know the codebase) but because the agent has to reconstruct understanding from scratch every single time.

Brooks was right that the conceptual structure is the hard part. We just never had to make it this explicit before.