'custom' part is the problem. Dealing with few vendor service APIs everyone has a different idea and syntax on how to implement simple AND, OR filter. Few weeks

'custom' part is the problem. Dealing with few vendor service APIs everyone has a different idea and syntax on how to implement simple AND, OR filter. Few weeks back spent half a day trying to figure out what the correct syntax is to do '<value> IN ...' query due to poor API documentation. Something more intuitive would be nice.