DotNext by .NET Foundation and Contributors

<PackageReference Include="DotNext" Version="4.8.1" />

 CustomAttribute

public static class CustomAttribute
Contains static methods for retrieving custom attributes.
public static bool IsDefined<TAttribute>(this ICustomAttributeProvider member, bool inherit = false) where TAttribute : Attribute

Indicates whether one or more attributes of the specified type or of its derived types is applied to the member.