Come on now. You're about to run their cli and let it send any random file on your machine to their API intentionally. Trust them a little.

There are a lot of fraudsters out there who will happily create thousands of accounts with valid CCs that will fail on first actual charge.[0]

I wouldn't be surprised if asking for a phone number lowers the fraud rate enough to compensate for the added friction.

[0] Incidentally, this is also why many AI API providers ask for your money upfront (buy credits) unless you're big enough and/or have existing relationship with them.