Rich text editing of the description, including link insertion, is available on the Light Plan and above.
Open the author editing screen
Select the text you want to turn into a link in the Description field
Click "Insert link" in the toolbar
Enter the destination URL
Choose whether to open the link in the same window or a new window
Click "Add link"
Note: https:// is required for external links.
To edit an existing link, place your cursor on the linked text and click "Edit link" in the toolbar. To remove it, click "Remove link."