Agendapost mode means: The active state of posting in which someone has dropped all pretense of balanced discourse and is now openly or covertly pushing a single narrative across their entire feed. Entering agendapost mode. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.