[GreyDog]

$(document).ready(function () {
            $("#table").jqGrid({
                url: "/api/gm/",
                datatype: "json",
                mtype: "GET",
                   
               //попробуй так
                jsonReader: 
                {
                    repeatitems: false,
                    id: "id",
                    page: "page",
                    total: "total",
                    rows:"rows"
                },

                colNames: ["id", "Name", "Alias"],
                colModel:[
                    {name:'id',index:'id', width:55},
                    {name:'Name',index:'Name', width:55},
                    {name:'Alias',index:'Alias', width:550}
                ],
                pager: "#tablePager",
                rowNum: 10,
                caption: "Group mapping Records",
 });
        });