Code inspection: Interfaces marked as ServiceContract should declare at least one OperationContract

This inspection reports an interface marked with [ServiceContract] that does not declare any [OperationContract] methods. That usually means the contract is incomplete and will not expose any service operations.

Example

                using System.ServiceModel;
                [ServiceContract]
                public interface ICalculator
                {
                    int Add(int x, int y);
                }
            

                using System.ServiceModel;
                [ServiceContract]
                public interface ICalculator
                {
                    [OperationContract]
                    int Add(int x, int y);
                }
            

Quick-fix

The quick-fix adds [OperationContract] to the interface methods.

01 April 2026