Specify as many or as few options as you go

gistfile1.js

        $.ajaxSetup({
            url: '/api/',
            type: 'POST',
            dataType: 'json'
        });

//------ e.g. 1, just need to specify data

        $.ajax({
            data: 'serverid=' + YAMS.admin.selectedServer + '&action=save-server-settings&' + $('#settings-form').serialize()
        });

//------ Or do a full request, but the next one will go back to defaults

        $.ajax({
            url: '/assets/parts/apps-page.html',
            type: 'GET',
            dataType: 'text',
            success: function (data) {
                $('#apps-tab').html(data);
            }
        });