Three working gadgets now exist whose electronics were designed by Anthropic’s Claude Fable 5.2. One is a speaker puck for video calls, one a box for a home voice assistant, and one a pocket virtual pet, and each started from a plain-language prompt. Human engineers built them from Claude’s files, and the boards ran without any circuit changes.
Claude’s job went well beyond drawing a schematic. It began each device with a written spec, then placed the chips, wired them with copper tracks, modelled a printable case, coded the firmware and listed the parts to buy. The speakerphone brief, for instance, was a single sentence asking for a puck with microphones, a speaker and Bluetooth over USB-C. The speakerphone has kept working for weeks since it was built.
The work was done with Diode Computers, a circuit-board maker that has a commercial relationship with Anthropic and built the boards. Anthropic’s research post says Diode’s engineers did the physical assembly because Claude was not connected to test gear or factory machines, and their prompting was limited to short nudges such as “continue”.
Anthropic says the big change from earlier models is geometry. Older models scattered helper components far from the chips that needed them and turned connectors around, and many boards ended up 95% finished but unusable. Fable 5.2 started with the signals most at risk from noise or speed, and it abandoned layouts that were going nowhere. On the hub it deleted and redid copper routes dozens of times, and it wrote its own grid-search router in about half an hour when the stock KiCad tool needed too much hand-holding for a 100-pin connector.
It also caught physical problems. Its own collision check found that the speakerphone board would not go into the case in one straight movement, since the mute switch caught on the rear wall, so it worked out that tilting the board by about 25 degrees would fit and wrote that step into the assembly instructions. For the hub, Claude worked out that a 25 mm sound channel to the microphone would resonate around 3.4 kHz, inside the range of the human voice, and a wedge-shaped case brought the channels down to roughly 10 mm.
On Diode’s PCB Gym layout benchmark, Fable 5.2 scored 69%, against 25% for Fable 5. On the public BenchCAD 2.1 test it scored 83.5%, nearly double Claude Fable 5.1.
These remain early prototypes. Nobody has yet run them through the checks a product needs before sale, from antenna tuning and heat tests to certification, and they were never meant for factory production. Anthropic’s next experiments involve more crowded, faster boards, checked in simulation first.
