<PackageReference Include="System.ServiceModel.Primitives" Version="8.1.2" />

System.ServiceModel.Channels.MethodCall

class MethodCall
namespace System.ServiceModel.Channels { internal class MethodCall { public MethodBase MethodBase { get; } public object[] Args { get; } public object[] InArgs { get; } public MethodCall(object[] args); public MethodCall(MethodBase methodBase, object[] args); } }