wpMandrill::mail > documentation?

Greetings.

I’m wondering if there’s any documentation on this method?

The application I’m working on currently is using it. I know what it does in general but I’m also not the original developer. The client has requested some enhancements and before I get in deep I was hoping there’s something somewhere that can save me a bit of time and headache, etc.

Thanks.

https://wordpress.org/plugins/wpmandrill/