Is there a way to register new terms into the list recognized by ok google?

I'm assuming the answer is "no" but thought I would just double check.

I'm curious if there's some way that my app can register a phrase to associate with itself so that when the user says "ok google MY CUSTOM PHRASE" it would wake up my app and pass it the string.

Specifically, I'm trying to re-create Siri's "add milk to grocery list" functionality which is (surprisingly) absent from the roster of Google's recognized features. I know there are apps that handle lists, but there's no obvious way (that I can see) to go from tapping the microphone once to adding an item to a list.

I don't need advice on how to recognize speech or anything of that nature, I get how to do this the "push a button in my app and speak" way. I'm specifically asking only about the OK GOOGLE phrases and whether or not there's some way I'm overlooking to add custom phrases to that dictionary.

As far as I know there are no APIs available for this (though it is possible on google glass: using unlisted commands).
Using two apps, Tasker and AutoVoice, you can actually create custom "ok, google" commands. See Lifehacker article for reference.