By #1237, a new column "twofa_scheme" that represents the two-factor authentication scheme enabled for the user. You can also know whether two-factor auth is enabled for the user by checking the column's value.

I think Users API should export the new column as well.

diff --git a/app/views/users/show.api.rsb b/app/views/users/show.api.rsb
index 3bc77e3be..5fe3d5b1c 100644
--- a/app/views/users/show.api.rsb
+++ b/app/views/users/show.api.rsb
@@ -9,6 +9,7 @@ api.user do
   api.updated_on @user.updated_on
   api.last_login_on     @user.last_login_on
   api.passwd_changed_on @user.passwd_changed_on
+  api.twofa_scheme      @user.twofa_scheme
   api.api_key    @user.api_key if User.current.admin? || (User.current == @user)
   api.status     @user.status if User.current.admin?

Possible values:

• null: Two-factor authentication is disabled
• "totp": Two-factor authentication with TOTP is enabled