Can a tulpa become a host

How does Tulpa communicate with its owner?

Lucid dreaming

Only people who are familiar with lucid dreams can communicate directly with a tulpa. When a person is unable to dream clearly, the best they can do is some vague interpretation of normal dreams that they can have that may or may not be true. For example, how would I know that a dream about an important conversation with a tulpa wasn't just some subconscious construct that had nothing to do with actually contacting them?

So I start practicing lucid dreaming so that I can distinguish between a dream that I actually control and a dream that is just an ordinary dream. At some point I get good enough that I can just ask a tulpa something that I couldn't possibly have known, to verify that the contact is real, and then test it during the day. One possible test could be that my wife hides my car keys somewhere while I go for a walk before bed so that my subconscious cannot dip the answer into my dreams. I ask the tulpa to tell me where they are, then wake up and find them exactly where they are. Okay, now I know that I am actually in contact with a real tulpa and that he is conveying real information to me.

Now Tulpas have names that act like the magical version of a web address. When a tulpa wants to keep me in touch they give me that name so I can call them up when I have a clear dream of consulting them, whatever I need. Obviously, it's not an exact science as tulpas honestly don't have a binding contract, but it's much more accurate now than regular dream interpretation which could turn out to be a random assignment of chance to unconscious gibberish.

This way you add a fun variation of powers to your story, as lucid dreaming is something that can be done easily, regularly, and naturally without effort by some, and a lot of training for others, or even a combination of both. They combine users with natural talents and people with training and people who just can't quite get it working.