How can I add a hyperlink as an attribute?
You should only use the hyperlink attribute type if you are linking to an external web application which uses a base URL and a parameter to identify each asset.
If you simply want to add a link to each asset you should add a new attribute of type ‘Textarea‘. On setting up the attribute you must check the box ‘Edit/show as HTML‘.
When editing the attribute value for an asset you can now use the HTML editor which allows you to embed hyperlinks.