Claude Fable 5.2 Produces Three Working Electronics Prototypes

Claude Fable 5.2 designed three electronic devices whose assembled prototypes worked without circuit corrections, demonstrating the model’s ability to handle tasks from board design to firmware preparation.

Diode Computers built a speakerphone, a voice-assistant hub and a handheld virtual pet under the model’s direction. With minimal prompting, Fable 5.2 produced specifications, schematics, printed circuit board (PCB) layouts, firmware and parts lists. The prototypes functioned after assembly without changes to their circuits.

The model scored 69% on PCB Gym, an internal test of component placement and connection routing. Fable 5 scored 25%. On the public BenchCAD 2.1 benchmark, Fable 5.2 scored 83.5%, nearly twice Fable 5.1’s result. BenchCAD 2.1 tests reconstruction of 3D parts and assemblies.

Fable 5.2 also revised designs while working. In the speakerphone design, it reassigned signals to different chip pins to optimize copper-layer use and prevent overcrowding. For the voice-assistant hub, it rerouted tangled connections. The board design also used tuned patterns and precise spacing for USB and Ethernet signals to keep their timing synchronized.

The prototypes are early-stage designs. Their long-term durability and compliance with commercial certifications have not been established, so the working builds do not establish whether the devices are ready for commercial use.

The hardware work adds to recent results for Fable 5.2, including its first-place showing on the AA-3D scene-generation leaderboard. That leaderboard result measured performance in a separate task from electronic design.