How to define a function reminding of names of the independent variables?

I am using a function with a lot of variables. There are 9 and sometimes more of them. In this case, it is difficult to memorize, which one stays on the, say, fourth position, and which one – on the seventh. I would like to be able to include the variable name into the square brackets of the function as a reminder: what must stay here.
For example, let us define a simple function: f(x)=x^2+y^3. Here is its definition:


One can, however, call it with x=5 and y=7 as follows:


This way reminds me of what should stay in the first and in the second position inside the square brackets.
This works, but I do not like that it looks cumbersome. For perception, it would be much better, if the (* and *) signs are invisible.

Any idea?