Switch to a new routine

Wednesday morning. You finished your last mesocycle and want to begin the new routine today instead of waiting for Monday. The agent knows about both routines — the one you just wrapped and the one you've been drafting.

What the agent needs to hear

Behind your sentence, the agent resolves the Routine plus three execution choices: when it ends (indefinite, inclusive date/weeks, or session count), weekly frequency, and IANA timezone. It asks only for missing choices. Activation always starts on the current local day; there is no scheduled state. The previous active Routine and engagement are paused atomically.

For a Tuesday–Sunday start, the agent first previews every local date remaining through Sunday. You choose one eligible workout or explicit rest for each date. It shows the complete week-zero proposal and activates only after you confirm the whole selection. The following Monday starts the regular weekly cycle; you do not need to wait for it to begin cleanly.

You can name the new routine the way it sits in your head — by title (« activate PPL v2 »), by descriptor (« the new push-pull-legs split »), or by what makes it distinct (« the one with the longer leg day »). The agent searches your saved routines for the closest match and shows you a card with the routine’s name, day count, and first week — and waits for a nod before flipping the switch.

What activation actually changes

A routine activation creates a new execution with an independent counter and history. Past sessions stay attached to their original engagement. Pausing and resuming retains that same engagement and shifts a date-range end by the union of pause and time off.

During week zero, adherence uses the workouts in the current effective dated plan rather than the normal weekly frequency. Rest dates do not count. If every remaining date is rest, the partial week is not evaluated rather than scored as 100%. A confirmed edit or time off can change that effective denominator before the week closes.

The previous routine moves to paused state. Paused routines aren’t deleted, archived, or hidden; you can reactivate them later if you want to cycle back. If you want it gone for good, that’s a separate action: « archive PPL v1 » after activating the new one tells the agent to clean it from your active list.

When the routine isn’t quite ready

Routines can be in draft state — exercises queued but the structure isn’t final, or you wrote down a week of training but haven’t filled in the rest. Activating a draft is allowed, but the agent will flag what’s missing: « PPL v2 has only week 1 filled in; want to activate anyway? ». If you say yes, the routine activates and the missing weeks behave as rest days until you fill them in. If you say no, the routine stays in draft and the active routine doesn’t change.

The same flag fires for routines with no scheduled days, no exercises in some days, or mesocycles without weeks defined. None of these block activation — they just warn so you know what’s coming.

When the agent gets it wrong

The card showing the activation preview is the chokepoint. If the agent picked the wrong routine (« PPL v1 », the one you just finished, instead of « PPL v2 »), name the difference more sharply: « no, the new one — PPL v2, the draft with longer leg day ». The card swaps to the correct one.

If the agent tries to proceed without showing you the complete dated preview, stop it before confirming: « wait, show me every workout and rest day through Sunday first ». The agent should present the full proposal without changing the active routine.

What makes a clean activation

Three things decide whether this switch lands cleanly: the right routine is the one now active (so today’s session queue matches what you mean to train), the complete week-zero selection is confirmed (so each remaining date is an intentional workout or rest), and the previous routine moved to paused, not deleted (so its history stays attached and you can cycle back). The system uses the active routine for the daily queue, mesocycle progression, and routine adherence; activating the wrong one quietly anchors every future session to the wrong template. Pick the routine the way you’d name it out loud, confirm the full dated proposal, then go.