GMAIL API : Authorize Every time you use the API

Question

Do you need to Authorize everytime before calling any Gmail API?

I have done authorization once and got the access Token and Refresh Token.

If I call the API's every minute for a user, do I need to Refresh the tokens everytime? If not, when should I do it again?

Answer 1

The access token is valid for one hour then you can use the refresh token to get a new access token without having the user to grant permissions again.

you can use the refresh token whenever you want to get a new access token, although it would be better to use it just before the access token expires.

Here is more documentation on that.