How to verify a token

Hi, I'm running a networked game using mirror. I need to authenticate users on my mirror server to verify that its actually them in the back end. I plan to send the user token to the server but i cant find a way to validate the token. I seen in the docs there is something called tuna but it looks like its a mircroservice that i would have to run. Is there any way to validate without running a microservice?

Thanks!