[nfriedly]

> there's also no way for a cable to communicate its current limitations

I don't think that's quite right. USB-C cables that support >60W (>3A @ 20V) must have an e-mark, which is a small chip embedded in the cable that identifies it as being able to support specific levels of power, such as 5A @ 20V for 100W or 5A @ 48V for 240W.

Spec-compliant chargers won't supply more than 60W unless the cable has the appropriate e-mark.

[zbrozek]

Good to know, thanks! I was interested in the comms side and not the cable side since I was considering building a widget that didn't use USB-C as the physical layer but did use PD for power negotiation.