I say this as someone that's writing a deployment toolkit for internal use. Their API is an ill-thought-out, illogical, and painful mess, and the more cynical side of me believes it to be that way on purpose. It's harder to get commoditized if you're harder to interop with.

Then again, it could just be cultural. It took years of people complaining about the awfulness of their web based admin tool before they decided to take those complaints onboard and deal with them; and those were the admins who have to use the thing every day, a much louder and larger group than annoyed developers.

http://docs.ansible.com/ansible/vsphere_guest_module.html

https://docs.saltstack.com/en/latest/ref/clouds/all/salt.clo...

My hat is off to their developers, about an hour of dealing directly with VMWare SOAP API was a prelude to a migraine.