{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://adcontextprotocol.org/schemas/3.2.5/enums/pixel-tracking-event.json",
  "title": "Pixel Tracking Event",
  "description": "Closed AdCP event vocabulary for renderer-fired pixel trackers. Impression and viewability values through `viewable_video_50` map to IAB OpenRTB Native event tracker types 1-4. `audible_video_complete` is an AdCP-defined first-class event, not an assigned IAB Native event type; Native reserves 500+ for exchange-specific use. `click` represents Native click trackers and `custom` is the explicit adopter-defined extension point.",
  "type": "string",
  "enum": [
    "impression",
    "viewable_mrc_50",
    "viewable_mrc_100",
    "viewable_video_50",
    "audible_video_complete",
    "click",
    "custom"
  ]
}