There's no API functions yet.

The key is in. More work needs to be done to add the functions that can be called to get your data. But that is independent to game client. You just need your key in the client to be able to...

Did you not read my 20,000th post? :)

It's to support Shadow Era API that can be used by external tools like deckbuilders to import or export your decks or tell you what cards you need or let you...