An example method includes: identifying message labels for electronic messages; identifying, based on a classification model specific to a first user, a first and a second message labels for a first and a second electronic messages; detecting a user action by the first user on the second electronic message to indicate the first message label is descriptive of the second electronic message; responsive to the user action, re-training the classification model based on tokens produced from the second electronic message to produce an updated classification model specific to the first user; after re-training is completed, detecting an incoming electronic message having a timestamp later in time than timestamps for the first and the second electronic messages; determining that the incoming electronic message shares a predefined number of tokens with the second electronic message; and assigning, based on the updated classification model, the first message label to the incoming electronic message.