Standards

Data Model

The v0.1 normative event type is glucose.reading. Future event types (alerts, device status, therapy events) are planned and listed on the Events page.

Required fields

Field	Description
`event_type`	Must be `glucose.reading`
`event_version`	Must be `0.1` for this schema generation
`subject_id`	Stable subject identifier in the producing system
`observed_at`	Clinical observation time (RFC 3339 UTC)
`value`	Numeric glucose value (> 0)
`unit`	`mg/dL` or `mmol/L`
`measurement_source`	`cgm`, `bgm`, or `manual`
`device`	Object with required `type` (`cgm`, `bgm`, `app`, `watch`)
`provenance`	Source system, raw event id, adapter version, ingested_at

Optional fields

source_recorded_at, received_at
trend — direction, rate, rate_unit
quality — status such as valid or questionable

Example

{
  "event_type": "glucose.reading",
  "event_version": "0.1",
  "subject_id": "local:iphone:demo-subject",
  "observed_at": "2026-03-29T14:32:00.000Z",
  "source_recorded_at": "2026-03-29T14:32:00.000Z",
  "value": 142,
  "unit": "mg/dL",
  "measurement_source": "cgm",
  "device": {
    "manufacturer": "Dexcom",
    "model": "G7",
    "type": "cgm"
  },
  "provenance": {
    "source_system": "com.apple.health",
    "raw_event_id": "A1B2C3D4-E5F6-7890-ABCD-EF1234567890",
    "adapter_version": "0.1.0",
    "ingested_at": "2026-03-29T14:33:15.000Z"
  },
  "trend": {
    "direction": "rising",
    "rate": 1.8,
    "rate_unit": "mg/dL/min"
  },
  "quality": {
    "status": "valid"
  }
}

Normative schema: glucose.reading.v0_1.json