Using the Tag Assistant
You use the Tag Assistant to mark a test class to search or retrieve the unit test later. You also use tags to view tests as a group in a particular development class. You can classify your tests, for example, as performance tests.
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1. To start the Tag Assistant, in the test browser, open the context menu of a test class and choose Tag Assistant.
In the upper screen area, the Tag Assistant displays this test class together with all tags currently assigned.
In the lower screen area, you see a list of all available tags and their values.
2. To assign tag values to a test class, select the required tag value in the lower screen area and drag-and-drop it to your test class in the upper screen area.

You can assign only one value of a given tag to a test class.
3. To create a tag, in the Tag Assistant, choose Create.

Tags are based on the general classification system. Any characteristic within the group ABAP_UNIT_TAGS is regarded as tag.

You can also cerate tags using the Characteristics Builder (transaction code SATTR)
You can search for the tagged test classes by using the search in the Test Browser.