Hi,
Sorry for not documenting these function better – many of them are only used “internally” in my solutions. Call the function like this:
var uRes = spjs_UpdateList(_spPageContextInfo.pageListId,_spPageContextInfo.webServerRelativeUrl,[{'Type':'Text','DisplayName':'THE_FIELD_NAME','AddToView':true}],[]);
“_spPageContextInfo.pageListId” is the current list GUID and the “_spPageContextInfo.webServerRelativeUrl” is the current list base url.
Alexander