I also have the AT&T C71 but it is a pure Android box, nothing in common with the Genie AFAIK. I tried manually adding it as Will suggested but that doesn’t work.
I found this quote in the ATT user guide. “The AT&T TV device is a game-changing, proprietary “Over-the-Top” (OTT) device that delivers video and integrated content to your TV over the internet. It enables you to watch online videos, listen to music, use thousands of third-party apps, and play games—all on your TV. It comes preloaded with some Google apps, but thousands of others are available at the Google Play Store.The AT&T TV is used on its own as a standalone device (one per TV) so you don’t need any other AT&T TV set-top boxes or services. (It’s not compatible with any DIRECTV set-top boxes or existing Genie® Servers.) It comes with a remote control offering many features, including the convenience of voice control.”
The manual goes on to state "The AT&T TV (C71KW) works with the RC82V Remote Control. (The box and remote control are not compatible with any older DIRECTV or AT&T U-verse® equipment.) The key features of the RC82V Remote Control are:
• The RC82V Remote Control works in IR and RF mode.
• Basic remote operations can be performed in the IR mode.
• The remote uses two-way communication to the AT&T TV.
• RF mode eliminates the need for the remote and the paired devices to be in line of sight to each other.
• The RC82V Remote Control has a directional pad. Basic operations and functions can be made by pressing the direction, then pressing ok.
• Once paired, voice recognition is also available with the RC82V Remote Control so you can use voice search
What I found will work is to let auto discover find it and add it as a Fire TV. It will also add the same IP address as Chromecast device but I haven’t used that in any activities yet. I do use the Fire TV device in my Watch ATT TV activity and it works pretty well. The standard Fire TV keypad covers more of the functions of the RC82V remote. I haven’t tried to use Google Voice yet. The one thing that is missing from the standard Fire TV UI is the RC82V has a button labeled … This works similar to the Options button on a Roku. So if you position the cursor over a show in the Program Guide and hit the … button it brings up a menu of options to Watch Now, Record, bookmark for later, or on some shows Watch from beginning. This is a unique feature of the AT&T TV Guide that I haven’t seen on other Android devices.
So my question is - is there any way to add this command to the standard Fire TV code? Or do I have to delete the Fire TV device and add the C71 manually and learn the IR commands from the RC82V in order to get all of the functionality of the ATT Remote? I have a IR blaster in my rack already with unused repeaters but would prefer to stick with IP commands, if possible.