Shows a model carrying a hardware design through schematic, PCB routing, enclosure CAD and firmware, with built prototypes working without circuit fixes. It marks agentic capability moving into physical engineering workflows.
Key takeaways · AI-distilled
Anthropic and Diode Computers, which has a commercial relationship with Anthropic, had Claude Fable 5.2 design a speakerphone, a voice-assistant hub and a handheld virtual pet from short prompts. Diode built all three from Claude's files, and they worked without circuit fixes.
On Diode's internal PCB Gym benchmarkA standard public test set for comparing AI models — the shared scoreboards behind every "model X beats model Y" claim.Full definition →, which scores component placement and routing on boards whose layouts were removed, Fable 5.2 scored 69% against 25% for Fable 5. On the public BenchCAD 2.1 it scored 83.5%, nearly double Fable 5.1.
Earlier models rarely revised their own layouts, leaving Diode boards 95% complete but unusable. Fable 5.2 changed course unprompted: it reassigned chip pins, re-laid a crowded board corner, and ripped up and rerouted tracks dozens of times.
When KiCad's built-in router, which draws one track at a time, proved too slow for long tracks from a 100-pin connector, Claude wrote its own grid-search router in about half an hour that laid each long track in roughly a second.
Anthropic says the devices are prototypes only: no electrical validation, antenna tuning, thermal testing or certification, and Claude had no access to test equipment or fabrication machines, so Diode engineers built and tested them.
Terms in this piece · Glossary
benchmark — A standard public test set for comparing AI models — the shared scoreboards behind every "model X beats model Y" claim.
