Note
This difference is often used to talk about different kinds of results in the present. The present perfect is used when the action is finished, and the result comes from the action being finished:
I've eaten dinner, so let's go out.
She's done all her homework, so she can relax this evening.
I've made a cake. Would you like some?
The present perfect continuous is used when the result comes from the action itself. It doesn't matter if the whole action is finished or not. The result is often something we can see, hear, smell, or feel:
I've been eating dinner, so there are plates all over the table.
She's been doing her homework, so she's tired.
I've been making a cake, that's why the kitchen is such a mess.