If you go to the JD Edwards Update Center in My Oracle Support, and then in the "News and Links" section at the bottom left, go to the EnterpriseOne Tools Releases page, it will give you a nice chart that shows the compatibility between tools and application releases.
On applications 8.12, you can only go as far as tools 8.98.4. You'll need to upgrade your release if you want to go to a newer tools release.