Schedule a reminder for the current user. At remindAt it is delivered to their Macro inbox as a notification and stays there until they mark it done. A reminder is either attached to one Macro item — so clicking it opens that item — or standalone. Attached is the common case (“remind me to reply to this email tomorrow”); standalone is for everything else (“remind me to book a flight”). Reminders are private: one is only ever delivered to its owner, and there is no way to set one for somebody else. Only one-off reminders can be created — if the user asks for a repeating one, say so rather than creating a single reminder and implying it repeats. ## Times are UTC — convert both ways Timestamps are absolute instants, in and out, while the user asks in their own timezone. Getting this wrong silently sets the reminder to the wrong hour. - In: resolve their wording against their local time, then convert. For America/New_York (UTC-4 in August), “3pm tomorrow” on 2026-08-12 is "2026-08-13T19:00:00Z", not "2026-08-13T15:00:00Z". - Out: report the response’s UTC value back in their timezone — "2026-08-13T19:00:00Z" is “3:00 PM tomorrow”. Ask for their timezone rather than assuming UTC. ## Attaching to an item Pass entityType and entityId together, using ids from ListEntities, GetThread, or search. The user must already have access to what you attach. entityType accepts exactly these values, and a type not on the list cannot be attached even if ListEntities returns it: - document — a Macro document - ai_chat — an AI chat conversation - project — a project, shown as a folder in the app - email — an email thread - channel — a chat channel - call — a call record - calendar_event — a calendar event A channel thread needs its parent channel’s id. channel is on the list; channel_thread is not. For a thread row, pass entityType: "channel" with the row’s channelId — never the thread’s own id, which will not resolve. Put what the thread is about in the description, since that is what tells two reminders on the same channel apart. For any other unattachable type, create a standalone reminder naming the thing in the description rather than guessing at a type.