My first conclusion is - the perl SDK doesn't actually seem to do anything much - it seems to be a reimplementation of LWP and and XML Parser. 

Given I have LWP and XML::Twig installed, and am making API calls just fine, is there anything I'm missing here? 

Aside from that though - authentication types. 

I currently use ssh public-private key pairs, in a trusted account on a management station to enable 'doing stuff' with filers. It _looks_ like my only option with the API is to create a designated service account, and assign permissions... and then embed a username and password in a script somewhere.
That just doesn't sit well with me - I like what ssh-agent will do in 'unlocking' key files, and I don't like embedding (potentially privileged) usernames and passwords ... anywhere.

Does anyone have a better solution than a couple of designated API users (privileged and read only) with a file somewhere embedding their username and password? 

Does anyone have a better approach?