Comment by leptons

Plain old Claude already does this fairly well, maybe not with up-to-date DB access though.

Claude helped me cut my BOM costs on JLCPCB/LCSC significantly by suggesting cheaper versions of the parts I was already using.

It also designed a new board for me for KiCad 10 (a brand new project), including all parts selection from JLCPCB.

I ended up not using JLCPCB for the PCBA, I only ordered blank PCBs from JLCPCB because cost of PCBA was too high for this project, so I had Claude redesign the schematic to use through-hole parts that I will assemble myself. I was able to source all the parts from Mouser and Amazon.