So here is what the method looks like now:
POST person/personId/edit
https://api.example.com/*key*/person/*personId*/edit?FName=Blah
I want this to change the first name of person at personId to Blah.
And if I need to add a person I say:
PUT person/create
https://api.example.com/*key*/person/create
and it will add a person with a new personId.
The general convention is usually:
A difference I can see is that you are also using different URIs, what is most commonly use is a single resource URI. But, anyways that’s debatable so it is a matter of how you like it.