<PackageReference Include="System.ServiceModel.Primitives" Version="8.1.0" />

System.ServiceModel.Description.IContractBehavior

public interface IContractBehavior
void AddBindingParameters(ContractDescription contractDescription, ServiceEndpoint endpoint, BindingParameterCollection bindingParameters)

void ApplyClientBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, ClientRuntime clientRuntime)

void ApplyDispatchBehavior(ContractDescription contractDescription, ServiceEndpoint endpoint, DispatchRuntime dispatchRuntime)

void Validate(ContractDescription contractDescription, ServiceEndpoint endpoint)