Rivesa R3 is a real agent: it plans, builds step by step and checks its work

The agent now runs on a live model through Vercel AI Gateway, with no API key to manage. It writes a plan, then builds in passes: it can start from a physics-checked PKD product, search the parts catalogue and fit real motors, propellers and batteries, add and move parts, group subsystems, add callouts and draft the one-pager or deck. Each step streams into the panel as it starts and ends, and the canvas grows with it, parts cascading in from the ground up while a Rivesa R3 cursor shows what it is working on.

It is built to be relied on: every tool checks its input and a failed step leaves the design as it was; when it finishes, a design it changed must pass the physics check or it gets the errors back to fix (up to two rounds); it is bounded in steps and time and always ends with what is on the canvas and where it stands. The whole reply is one undo step, and Stop ends it at any point. Claude needs AI Gateway credits on the Vercel team; until they are added it runs on GPT-5 mini and says so.