while I am testing the Windows 10 Beta App, I noticed some items without any details. Most of the items are from the category "bonus program card" or "Software license" and the items are older (from 2013 and older).
In 1Password 4 for Windows I can see all details. I use the agilekeychain format.
1Password Version: 2016.4.2600
Extension Version: Not Provided
OS Version: Windows 10 10586.218
Sync Type: Dropbox