The UI Spy tool enables developers and testers to view and interact with the user interface (UI) elements of an application.
By viewing the application's UI hierarchical structure, property values, and raised events, developers and testers can verify that the UI they are creating is programmatically accessible to assistive technology devices such as screen readers.
UI Spy uses the UI Automation libraries. UI Automation is the new accessibility framework for Microsoft Windows.
The UI Spy tool is obsolete and no longer available. Developers should use other tools such as Inspect.exe that are available in the Windows Software Development Kit (SDK). For more info, see Testing Tools.
source: https://msdn.microsoft.com/en-us/library/ms727247.aspx