session.getSiteCategoryContents

Hello.
I'm working on a SSP applciation, using CommerceAPI (SiteBuilder, NO SuiteCommerceAdvanced).

My page is on the shopping domain, the user is not authenticated.
I want to retrieve all the item filtered by "site category".
From the documentation, i'm trying to call the "getSiteCategoryContents" API, but i'm getting an error:

test1) session.getSiteCategoryContents(true);   --> WORKING FINE

test2) session.getSiteCategoryContents([{"internalid":"10513"}]);    --> ERROR:Can't find method $Proxy99.getSiteCategoryContents(object)

test3) session.getSiteCategoryContents([10513]);    --> ERROR:Can't find method $Proxy99.getSiteCategoryContents(object)

test4) session.getSiteCategoryContents(10513);    --> ERROR:Can't find method $Proxy99.getSiteCategoryContents(Number)

test4) session.getSiteCategoryContents('10513');    --> ERROR:Can't find method $Proxy99.getSiteCategoryContents(String)