Laravel 5.5: How to protect the register route in a stateles API and make sure that a real person is trying to register throught a mobile app?

I want to protect my register route so only real users of mobile applications can register and I will not get spamed with thousands request for registration. I know laraval takes care of this throught csrf token but that is only for web applications where we have sessions. How about stateles Api? How can i exchange an application token when the user is trying to register for the first time from mobile application?

via Chebli Mohamed