1. A method comprising: receiving a request comprising a join timestamp representing when a target user joined a live stream and a request time point representing a break in the live stream; applying a predictive model to a join duration that represents a difference between the join timestamp and the request time point to generate a predicted attention score for the target user, the predicted attention score representing a perspicaciousness of a predicted user at the request time point; determining whether the predicted attention score is greater than a threshold score; and responsive to the determination that the predicted attention score is greater than the threshold score, retrieving a content item from a first content category of a plurality of content categories; and providing the retrieved content item to the target user during the break in the live stream.