>A computer can hold far more in “working memory” than a human can

That's a bit of a straw man. State of the art agents are limited to ~3.8Mi (1M tokens). That's usually where I run into issues--an LLM can't possibly hold as much context as a human and it's more of an art than a science getting the most important things squeezed in. It's especially prudent for complex codebases/systems.

An agent only knows what it can see. It doesn't know oldCruftyFunction is still critical to Bob's Excel macro that generates financial reports and yanks the codebase in as a bastardised dependency. A lot of times agents give a fall sense of security by making it seem like something complicated and unsafe is actually safe.

That's why you make sure to put that institutional knowledge in AGENTS.md /s