doc for init in vb()

There's no doc for initialization in the vb() command, but it allows the argument.

And if I give it bogus arguments, I get this:

> vb(foo="bar")
Error in (function (classes, fdef, mtable)  : 
  unable to find an inherited method for function ‘vb’ for signature ‘"missing"’

Is there a way to make a cleaner error message of some kind? If I give it one known argument and an unknown one, it provides the right kind of message (with behavior for unknown arguments matching R's own lm() function):

> vb(sm, foo="bar")

This is Automatic Differentiation Variational Inference.
...
In addition: Warning message:
passing unknown arguments: foo. 
> 

Start at the vb() entry point and inspect its existing argument handling and documentation. Reproduce vb(foo="bar") and the mixed known/unknown argument case to understand the current behavior. Done means documenting initialization arguments and defining or recording a clearer response for invalid-only arguments.