TVector3 Class documentation

Dear Root-Team,
Generally the documentation of root class is quite self-explicit, but
But for TVector3 some useful information is missing … r3:RotateY
For instance here :

Without knowing what is the Double_t , even if this is quite trivial to guess.
The only way to be sure is to click on the function to see the source

I guess this feature is related to the inline function and can also happen in more complex case.
Would be nice to always have an explicit class documentation.