registerForActivity

The reserved spot being bought, for a session selling against a spot map. The caller must already hold it — pass the same holderKey given to holdSpots, or the registration is refused as a lost race.

The checkout key the spot holds were taken under. Required with spot.

The general-admission section being bought into, for a spot map whose section sells as a capacity pool rather than assigned spots. Mutually exclusive with spot.

Register someone else, with the caller as the booker. Requires a signed-in caller. Omit guest.email to book without notifying the attendee — see GuestRegistrationInput.

Register one of the signed-in viewer's managed children (a FamilyMember with role child). The viewer must be a manager or guardian sharing a family with the member; the booking is recorded with the viewer as the booker and the child as the participant. Mutually exclusive with guest.

Optional discount code typed by the customer. Validated server-side against the activity's business; an invalid or unmet code returns a per-field error rather than registering at full price.

Optional gift-card code to apply against the registration price. The card's remaining balance covers up to the post-discount line; any remainder is charged via Stripe.

Stripe PaymentMethod ID captured via SetupIntent for paid card waitlists. Required when the registration falls onto the waitlist for a card-paid activity (no productPurchase); used to charge the customer off-session if their spot is later promoted.

When true for a signed-in card checkout, attach the newly-entered card to the buyer's Stripe Customer for future purchases. Ignored for guest checkout and saved-card waitlist reservations.

Stripe Tax calculation ID returned by a recent quoteTax query. When provided, the server reuses that calculation. Ignored when the seller has tax disabled.

Optional gratuity in cents. On a paid registration it rides the same charge, added after tax; on a pass/membership-covered one it mints a tip-only checkout instead of confirming immediately — the registration (and the pass debit) then commits only once the tip payment succeeds, so an abandoned checkout registers nothing. A tip is always excluded from both the tax base and the platform-fee base, and ignored for a waitlist join or a registration with no session. Tipping is per-activity: an activity that does not accept tips rejects a non-zero tipAmount outright. Classes, sessions, leagues and tournaments default to not accepting tips; bookings default to accepting them.

Email-marketing opt-in captured on the registration form. true records an affirmative consent for this participant against the activity's business; only honored when the business has consent collection enabled. Sessions never sends marketing email itself — consent lets the business email the participant through its own provider.

Version of the consent disclosure the buyer was shown. Frozen with the consent record so the proof reflects exactly what they agreed to.

Marketing attribution captured client-side (UTM parameters, referrer host, landing path). First-touch is stamped onto a newly created participant; last-touch onto the registration. The server classifies the trustworthy origin — a client-claimed marketplace origin is never trusted.

Opaque client-generated idempotency token, stable for one checkout attempt (e.g. a single crypto.randomUUID() minted when the payment step mounts, NOT regenerated per click). When provided, it is used as the Stripe idempotencyKey on the saved-card off-session charge so a double-submit / client retry deduplicates to a single live charge instead of charging twice. Omit it to keep the legacy behaviour.