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src/Features/Core/Portable/AddImport/CodeActions/ProjectSymbolReferenceCodeAction.cs

@@ -8,6 +8,12 @@ namespace Microsoft.CodeAnalysis.AddImport
 {
     internal abstract partial class AbstractAddImportCodeFixProvider<TSimpleNameSyntax>
     {
+        /// <summary>
+        /// Code action for adding an import when we find a symbol in source in either our
+        /// starting project, or some other unreferenced project in the solution.  If we 
+        /// find a source symbol in a different project, we'll also add a p2p reference when
+        /// we apply the code action.
+        /// </summary>
         private class ProjectSymbolReferenceCodeAction : SymbolReferenceCodeAction
         {
             /// <summary>