In general, indices in MAXScript are 1-based.
Functions expecting a 1-based index will specify this as <index> in the function definition.
<index>listIndex: The index of the item for which to get the name.
In the cases where a function requires a 0-based argument, it will be specified as <integer> instead. Usually, the fact that the argument is expected as 0-based will also be noted explicitly in the description of the function.
Returns a specific element, index is 0 based.
Syntax Definitions in This Document