Comment by stavros

I agree with the argument that there are many more than two ways to do this. When I built my AI assistant (https://stavrobot.stavros.io/), for example, I implemented an architecture that has both the ways detailed in the post. The harness runs simultaneously both inside and outside the container (I didn't want the harness to touch the system, and I didn't want LLM-generated code to touch the harness).

It's all tradeoffs, and picking the ones that work for what you want to do is what architecture is. The more informed you are about the tradeoffs, the better you can make your architecture.