This page of ReSharper options helps you obtain code annotation attribute classes as well as to make related configurations.
|JetBrains Annotations - official NuGet package
|Click this link to go to the JetBrains ReSharper Annotations home page where you can obtain the annotations using NuGet.
|Automatically propagate annotations
If this check box is selected, some ReSharper features will automatically insert
annotation attributes. For example, the
'Check parameter for null'
context action will add the
[NotNull] attribute in addition to generating code that checks for nullness.
|Default annotation namespace
|Allows you to choose the namespace where ReSharper looks for code annotation types. This option may be helpful if you have the same annotation types in several namespaces. For more information, see Annotations in Source Code.
|List of namespaces with code annotation attributes
ReSharper automatically detects namespaces in the solution and referenced
assemblies with valid annotation attribute types and displays the list of these namespaces, if any.
There may be cases when your solution contains several implementations of the annotation
attributes, e.g., you have classes with the same names as ReSharper annotations classes
|Annotations source code
In this section, you can copy the whole implementation of the
namespace to clipboard so that you can insert it in the desired place in your solution.
Before copying the annotations, you can customize the classes in two ways: