pass_series.leg_added

When this fires

A Pass Series with Automatic Passes Selection matched a newly-scheduled window on one of its source plans, added it to the slate, and granted it to everyone currently holding the series — at no extra charge.

This is the event that makes an external calendar or CRM worth wiring up. A season composed with rules is not fixed at the point it sold: it grows, and holders are given what it grows by. Without this you would have to re-read the plan to notice.

Holders are messaged too

Every current holder receives a Telegram message naming the new date, and it appears on their timetable and in their calendar feed. Nothing is asked of them — their invite link arrives before it opens, as usual.

Required ability

project-subscription-plan:view — token must carry this at mint time to subscribe an endpoint to this event.

Payload

{
  "id": "evt_01HX...",
  "type": "pass_series.leg_added",
  "created_at": "2026-10-04T07:15:00Z",
  "api_version": "2026-05-01",
  "project_id": "7f3d1c92-8b45-4e6a-9d21-5c8e0a4b6f13",
  "data": {
    "plan_id": "c4e82f16-93a7-4d5b-b81c-6e0f27a94d3b",
    "plan_name": "Autumn Season Ticket",
    "window_id": "3d5a8c72-b016-4e94-8fa7-61c209d4e738",
    "source_plan_id": "9a4c1b58-2e37-4d80-b6f1-0c7e35a92b41",
    "starts_at": "2026-11-08T18:00:00Z",
    "ends_at": "2026-11-08T21:00:00Z",
    "timezone": "America/New_York",
    "window_count": 12
  }
}

Field reference

Field	Type	Notes
`id`	string ULID	Unique event id, prefixed `evt_`. Use for idempotent processing.
`type`	string	Always `pass_series.leg_added` for this event.
`created_at`	ISO 8601 timestamp	Server-side emission time.
`api_version`	string	Webhook API contract version.
`project_id`	string UUID	Project this event belongs to.
`data.plan_id`	string UUID	The series plan that grew.
`data.plan_name`	string	Its name.
`data.window_id`	string UUID	The window that was absorbed.
`data.source_plan_id`	string UUID	The pass plan the window belongs to. This is the plan whose resources that date grants.
`data.starts_at`	ISO 8601 timestamp	Window start, always UTC.
`data.ends_at`	ISO 8601 timestamp	Window end, always UTC.
`data.timezone`	string	The source plan's authoring zone — a series has none of its own. Render the timestamps in this.
`data.window_count`	integer	The slate's total length after this absorption.

Caveats

This fires once per window. One absorption run can take in several at a time, which arrives as several events rather than one carrying a list.
Absorption respects Prevent Overlapping Passes. With the toggle on, a window that clashes with something already on the slate is refused rather than absorbed — the series will not hand holders two things at the same time — so a matching window can exist and never produce this event.
A rule of type next_n stops once it has taken its count and never tops itself back up. A window becoming free later does not make it reach for another.
A series is capped at 120 dates. A rule that would take the slate past the cap stops there.
Holders who cancelled are not granted the new date.
Manually handpicked dates never produce this event. Handpicking is a fixed list by design; only rules keep working after the save.
A date the creator has excluded stays excluded. Unticking a rule-added pass records a permanent exclusion, and the rule will not put it back.

pass.window_scheduled — the window coming into existence, which is what a rule reacts to.
pass_series.leg_substituted — a date being swapped rather than added.
pass_series.leg_dropped — a date leaving a season.
Pass series events overview — back to family overview.