Anthropic’s Claude Fable 5.2 designed three electronic devices from scratch, and all three worked on their first build. The AI handled circuit board layouts, component selection, 3D enclosure design, firmware coding, and full manufacturing checks. Anthropic published the results on November 9 alongside hardware partner Diode Computers.
Specifically, Anthropic asked Claude to design and build a USB speakerphone, a voice-assistant hub, and a handheld virtual pet.
For each device, the company gave Claude a simple prompt describing the product and its core hardware requirements. From there, Claude wrote full specifications, drew schematics, placed components on four-layer circuit boards, and routed all copper connections. It also designed 3D-printable enclosures and wrote the firmware for each device. Diode then manufactured all three boards directly from Claude’s design files without a single revision round. That outcome surprised the Diode team because factories and engineers typically require multiple adjustment cycles before production.
On benchmarks, Fable 5.2 scored 69% on Diode’s internal PCB Gym placement test, compared to just 25% for Fable 5. Additionally, it hit 83.5% on BenchCAD 2.1, a public benchmark for reconstructing circuit boards from engineering drawings. That score nearly doubles what Claude Fable 5.1 achieved on the same test.
What separates these results from earlier AI hardware experiments is the depth of reasoning Claude applied throughout each design. Claude routed high-speed USB and Ethernet connections first while keeping paired tracks equal in length for signal integrity. When layouts became too crowded, it deleted and rerouted dozens of connections without any human prompting. Furthermore, Claude calculated that a 25mm microphone port on the voice hub produces resonance at 3.4 kHz inside the speech band. In response, it redesigned the enclosure into a wedge shape that pushed resonance above speech range to 8.9 kHz.
However, all three devices remain early prototypes that have not undergone electrical validation, antenna tuning, or commercial certification. Human engineers at Diode still handled all physical construction because Claude lacked direct access to assembly equipment.
