>only at the system level, not the individual llm level.

Which is why llms aren't agents and depend on harnesses. The llm itself doesn't have a continual loop built in, that would be very power hungry. The harness works as the orchestrator of memory and action. Now, I can't think of a reason why an LLM couldn't bootstrap its own harness, but in general it sounds like a very dumb idea to actually build that from an AI safety perspective.

This discussion falls under the idea and refutation of the Chinese Room. The room may have no idea what Chinese characters are, but the system does.