How do I create a hook to a file card button using

I'd like to create a file card button hook. Follwoing the documentation, it looks like I should be able to do this using the AddHook method of IEdmCmdMgr5, and passing the EdmCmdType value of "EdmCmd_CardButton".

The documentation for this enum provides the following description:

EdmCmd_CardButton

37 = The user clicked either OK or a button whose command is enclosed in brackets ("<...>") in the file data card

Where I'm struggling, is how to get a bracketed command into the button in the first place.

Any time I try to type anything in brackets, the card editor automatically changes the `Command Type` property from "Command String" to "Run Add-in".

This automatically changes the input field name from `Command` to `Add-in name` and automatically removes the brackets from whatever I typed.

So am I supposed to just let the card editor do it's thing and not worry about enclosing a command in brackets?

If so, what then am I supposed to enter in the `Add-in name` field? Do I enter the name of my add-in, the name of the DLL, the name of the procedure, any arbitrary value, etc?

To be clear, I do not want to run a standalone add-in .exe. I've written an add-in library and I want to create a hook so I can listen for button press event and do something using the OnCmd method.