Question: when to use sum vs. SumTools?

Is package SumTools supposed to be a superset of the sum command in Maple? Or is it supposed to be a complementary to it? When should one use SumTools vs. sum?

The help on SumTools says

The SumTools package contains commands that help find closed forms of definite and indefinite sums. The package consists of three commands and three subpackages.
 

But does not make it clear when to use it vs. sum or what is its relation to sum command.

I am asking because on one example, sum is able to give an answer, while SumTools can't. I have expected the other way, where if sum failed, then one will try SumTools.

restart;
sum(1/n*sin(n*x),n=1..infinity) assuming 0<x,x<Pi

SumTools:-IndefiniteSummation(1/n*sin(n*x),n=1..infinity) assuming 0<x, x<Pi