public interface IGPResult 

//The data referenced in this snippet can be downloaded from the arcgis-pro-sdk-community-samples repo
//https://github.com/Esri/arcgis-pro-sdk-community-samples
async Task<IGPResult> CreateRings(EditingTemplate currentTemplate)
      {
          var paramsArray = Geoprocessing.MakeValueArray(currentTemplate.MapMember.Name,
                      @"C:\Data\FeatureTest\FeatureTest.gdb\Points_MultipleRingBuffer",
                      new List<string> { "1000", "2000" }, "Meters", "Distance",
                      "ALL", "FULL");

          IGPResult ringsResult = await Geoprocessing.ExecuteToolAsync("Analysis.MultipleRingBuffer", paramsArray);
          var messages = string.IsNullOrEmpty(gpResult.ReturnValue)
                  ? $@"Error in gp tool: {gpResult.ErrorMessages}"
                  : $@"Ok: {gpResult.ReturnValue}";

          return ringsResult;
      }

//The data referenced in this snippet can be downloaded from the arcgis-pro-sdk-community-samples repo
//https://github.com/Esri/arcgis-pro-sdk-community-samples
string in_data = @"C:\tools\data.gdb\cities";
      string cities_buff = @"E:\data\data.gdb\cities_2km";

      var valueArray = Geoprocessing.MakeValueArray(in_data, cities_buff, "2000 Meters");

      // to let the GP tool run asynchronously without blocking the main thread
      // use the GPThread option of GPExecuteToolFlasgs
      //
      GPExecuteToolFlags flags = GPExecuteToolFlags.GPThread;  // instruct the tool run non-blocking GPThread
      IGPResult bufferResult = await Geoprocessing.ExecuteToolAsync("Analysis.Buffer", valueArray, null, null, null, flags);