No, this is not the official Clavis Aethiopica. It is a nifty viewer that uses a static site generator to make it easier to view data from the actual Clavis, which is a part of the Beta maṣāḥəft project. Because it's a static site, it loads relatively quickly and works even when Beta maṣāḥəft's server is down.
This site was conceived and coded by Augustine Dickinson.
The code for this site is licensed under the MIT License.
The data from Beta maṣāḥǝft is licensed under the Creative Commons Attribution-ShareAlike 4.0 International License.