a16z's Yoko Li on the promise of agents that finish their own loops: "An AI model can almost always produce another answer." "It can revise the paragraph again. It can try another implementation. It can generate another image with more detail, different lighting, and a stronger composition." "This is part of what makes the recent idea of loop engineering so compelling. Instead of a human prompting a model, inspecting the result, describing what went wrong, and prompting it again, we can ask…