Droid 1.0: Building a Frontier Harness

Factory released Droid 1.0, an agent harness it says outperforms native harnesses built for their models by up to 20% more efficiently on the same tasks, with programmatic tool calling (Script mode) now the default for models including GPT-6.1 Sol, Claude Opus 5.5 and Kimi K3. The post reports that Script mode cuts Droid's cost by 15% on Claude Opus 5.5, that the base prompt shrank 37% between versions 0.170.0 and 0.250.0, and that median time to first paint fell from 1,839 to 488 ms. It also describes the internal Agent Factory loop, in which agents propose harness changes that engineers review before shipping.