Update to add revised AI use case (#49139)

* Update to add revised AI use case

* Add custom tag for Copilot scenario highlighting

Added a custom tag for highlighting Copilot scenarios.

Author: anandmeg

docs/csharp/programming-guide/classes-and-structs/how-to-initialize-a-dictionary-with-a-collection-initializer.md

@@ -1,11 +1,12 @@
 ---
 title: "How to initialize a dictionary with a collection initializer"
 description: Learn how to initialize a dictionary in C#, using either the Add method or an index initializer. This example shows both options.
-ms.date: 02/12/2025
+ms.date: 10/14/2025
 helpviewer_keywords: 
   - "collection initializers [C#], with Dictionary"
 ms.topic: how-to
 ms.assetid: 25283922-f8ee-40dc-a639-fac30804ec71
+ms.custom: copilot-scenario-highlight
 ---
 # How to initialize a dictionary with a collection initializer (C# Programming Guide)
 
@@ -30,6 +31,25 @@ In the following code example, a <xref:System.Collections.Generic.Dictionary%602
 
 Note the two pairs of braces in each element of the collection in the first declaration. The innermost braces enclose the object initializer for the `StudentName`, and the outermost braces enclose the initializer for the key/value pair to be added to the `students` <xref:System.Collections.Generic.Dictionary%602>. Finally, the whole collection initializer for the dictionary is enclosed in braces. In the second initialization, the left side of the assignment is the key and the right side is the value, using an object initializer for `StudentName`.
 
+## Use AI to generate test data for dictionary collections
+
+You can use AI tools, such as GitHub Copilot, to quickly generate dictionary test data and validation scenarios in your C# projects.
+
+Here's an example prompt you can use in Visual Studio Copilot Chat.
+
+```copilot-prompt
+Generate data collections for tests to create a separate Dictionary<int, Student> containing 10 valid Student records and 5 invalid records. 
+- Valid records should have realistic Name and Grade values.
+- Invalid records should include cases such as missing Name, Grade < 0, or Grade > 100. 
+- This dictionary should be used only for testing purposes and not modify existing production code.
+- Generate test code that utilizes this test data for validation scenarios.
+- Call test method to run the test.
+```
+
+Review Copilot's suggestions before applying them.
+
+For more information about GitHub Copilot, see GitHub's [FAQs](https://github.com/features/copilot#faq).
+
 ## See also
 
 - [Object and Collection Initializers](./object-and-collection-initializers.md)