Claude Fable 5.2 Routes Functional PCBs

The breakthrough is not merely drawing traces; it is Fable recognizing bad layouts, rewriting its routing strategy, and coordinating software, hardware, and manufacturing constraints. Still, the viral framing overstates the result: these were four-layer prototypes, not production-ready six-layer boards.

• –Fable scored 69% on Diode’s PCB Gym benchmark, versus 25% for Claude Fable 5.
• –It wrote a custom grid-search router when KiCad’s built-in routing became inefficient.
• –Human engineers still assembled and tested the boards; electrical validation, thermal testing, antenna tuning, and certification remain unresolved.
• –Hardware engineers may shift from manual routing toward constraint definition, review, simulation, and validation.
• –Independent builders are already extending Claude into Altium and KiCad workflows, suggesting an emerging AI-native EDA stack.