Client-server hybrid A.I. scores for customized actions are described. A client generates client scores corresponding to client customized actions by applying a user-specific model to an action received from a user, the user-specific model based on at least one historical action received from the user. The client requests a server to provide server scores corresponding to server customized actions by applying a cross-user model to the action received from the user, the cross-user model based on historical actions associated with server users. The client generates hybrid scores corresponding to hybrid customized actions by combining the client scores with the server scores, in response to receiving the server scores from the server. The client causes the hybrid customized actions to be outputted based on the corresponding hybrid scores.