If you are asking whether the data type of the elements in an array can be specified, no they cannot. In current the stable version of the engine (e.g. 3.5) the data type of the individual elements of an array can't be declared. IIRC, in Godot 4 they can be.
In the meantime (until Godot 4 is released), why not try using PoolIntArray
for the argument? While it may have setbacks, all of the elements of the array are only integers.