public DevParksMutation(ParkService parkService) { _parkService = parkService; var args = new QueryArguments( new QueryArgument <IdGraphType> { Name = "rideId" }, new QueryArgument <StringGraphType> { Name = "waitTime" }); Field <RideType>("updateWaitTime", arguments: args, resolve: context => _parkService.UpdateRideWaitTime( context.GetArgument <string>("rideId"), context.GetArgument <string>("waitTime"))); }