Recent research suggests that in visual analytics tasks, collaborative sensemaking relies on successful collaboration between humans and software agents. To advance the understanding of such collaboration, we consider that the latter possess a form of situational awareness which, when coordinated with humans, can enrich the collaborative sensemaking process. We propose a conceptual model for a coordinating agent that dynamically initiates interruptions, influenced by the analytic activities of humans. We provide possible designs for four coordinating strategies. In closing, we discuss plans for implementation, and how future studies can contribute to wider HCI and CSCW discourses.