Agentic Harness Engineering White Paper
Artificial intelligence is entering a new engineering phase. For the last two years, the dominant conversation centered on prompt engineering: how to ask better questions, structure better instructions, and squeeze more reliable output from large language models. That work mattered, and still matters. But as models have become capable of planning, tool use, coding, browsing, testing, and acting over many steps, the practical bottleneck has shifted. The central production problem is no longer simply how to prompt the model. It is how to build the runtime around the model so that the model can act effectively, safely, durably, and measurably. ...