To open the achievements menu, use the toggleInterface function.
Unlocking an Achievement
When a player reaches an important milestone in-game, reward them by giving them an achievement.
See the achievementSave reference for optional arguments.
Getting Achievement Data
Calling the achievementsList function provides a list of all achievements of the game. The list can be checked for a player property. If an achievement has a player property, that means the player has unlocked it. The data is returned to the handleIDNET function as an object.
See the page about achievement response data for details about unlocked achievements.