In Clarity version 16.4.1 "Enable AI" tab is not visible in the "VAIA" module within Modern UX Administration page.
How do users configure attribute to be used by AI?
Clarity 16.4.1
With Clarity 16.4.1, the functionality of 'Enable Ai' that is used for Gen AI capabilities is merged in 'AI Agents' tab.
If you click on 'New Agent' button and specify 'Type' field as 'Project', 'Context' as 'Attribute' then you can select from the Attribute field as shown in screenshot below then you can create a rich text field or use the Project 'Description' field as AI attribute if you specify these in the 'Attribute' field and also specify 'Output Location' as 'Text Field'.
To add a custom field or other field to be "AI" enabled, first create an Object attribute with Data Type set as - 'Large String - Rich Text'
For example, in a Project object, create a Rich text attribute.
When you create a 'New Agent' select 'Type' as Project (for example). 'Context' as Attribute. 'Output Location - 'Text Field'.
In the 'Attribute' field, select the rich text attribute created in the Project object.