When warlock chooses a pact with The Great Old One, he gains a feature called Awakened Mind:

Starting at 1st level, your alien knowledge gives you the ability to touch the minds of other creatures. You can communicate telepathically with any creature you can see within 30 feet of you.

My question is, is the communication two-ways, or only one-way?

I assume it's only one-way: I can "send" messages to target creature's mind but I can't receive any responses. So it's not possible for this creature to "send" me back any thoughts or messages and I can't read any of the creature's thoughts.