Map features API and values filter

Hi all,

The API documentation says that it’s possible to filter searched map features using the “values” parameter:
values : Filter map features by values. Values are groupped by layers. See the corresponding values for each layers.

But I’ve not seen anything about the syntax of this parameter. Is it a comma separated list? Moreover looks that wildcard works for exemple “values=object–traffic-light*” seems to return traffic lights of all categories.

Is there some documentation saying what’s possible with this param?