https://docs.microsoft.com/en-us/dotnet/api/system.componentmodel.dataannotations.validationattribute?view=netcore-3.1
vs
https://github.com/dotnet/runtime/blob/master/src/libraries/System.ComponentModel.Annotations/src/System/ComponentModel/DataAnnotations/ValidationAttribute.cs

For example, the latter's doc comments for IsValid(object) state that "Derived classes should not override this method as it is only available for backwards compatibility." but this does not appear on MSDN.

Additionally, the code claims that NotImplementedException is thrown if IsValid(object, ValidationContext) has not been implemented by a derived class, which is obviously incorrect.

There are numerous other differences.

Please can the source and documentation be made consistent to reflect how ValidationAttribute should work and be used by developers.