The variables apply when you use the Template mode. You can build your alt text from any of these variables:
Color
Product Name
Product Handle
Product Type
Variant
Filename
Vendor
Choose any combination and the app builds the alt text in that order (for example, “Dark Slate Gray Small Hours Beanie”).
If you prefer not to build a format yourself, you can switch to AI mode and the app writes natural, descriptive alt text for you automatically based on the product details you have — no variables needed.