How to handle token expiration?

Hi, i'm wondering how other people is handling token expiration on their apps. I used to base mine on when you get the Need Sign In error back in the call, but, all the PUBLIC end points don't behave like that, if you are logged in they return more info than when you are not logged in, but no error is present. I talked with VThron a few months back and he said that if you check the cookies on the response and the bungle token is not set as a cookie then you need to log in, but, i see that some end points like "User/GetBungieNetUser/" and "User/GetMembershipIds" don't have the cookies set on the response, so, after i log in it tells me i need to log in again, because no cookie is set. Are you guys hardcoding that only checks for other end points or is there a better way of doing this.