It seems that Microsoft has not taken the time to make Office Add-in Tool independently available. For instance With Internet Explorer you can Disable Add-ons easily by going to Windows Control Panel and launching Manage Add-ons Dialog by the way of Internet Options Dialog.
A typical symptom of a malfunctioningAdd-in for Microsoft Word is an unexplained crash of Microsoft Word. The issue can be resolved by launching WinWord.exe in safe mode. Because when you launch Microsoft Word with /safe flag from Command line it loads The Word Software with No add-ins. Word Safe Mode also refrains from loading Templates or contacting the cloud (OneDrive). This enables you to access Word Options Dialog which hosts an Add-ins Pane even when the Add-in is misbehaving. From there one can press the Go Button with Manage Com Add-ins to remove a malfunctioning Add-in. Here is a link to documentation that shows how to launch Microsoft Office in Safe Mode.
Figure 1: How to Launch Word 2013 in Safe Mode form Command line.
Figure 2: Microsoft Word Option Dialog with Add-ins pane selected.
Figure 3: Internet Options Manage add-ons that can be indecently launched from control panel.
I hope Microsoft at the very least adds Microsoft Office Options Dialogs to Windows Control Panel. Word, Excel, Notes, Can add in Options Dialog as an option in Jump Lists.
It should not be so hard for a non-technically savvy user to disable a Word Add-in.