{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://yukart/schema/envelope.json",
  "title": "Signal envelope",
  "description": "Every decoded signal published on yukart/vehicle/* and yukart/gnss/*. Raw CAN uses the binary frame encoding instead.",
  "type": "object",
  "required": [
    "timestamp",
    "monotonic",
    "value",
    "unit"
  ],
  "additionalProperties": false,
  "properties": {
    "timestamp": {
      "type": "integer",
      "description": "UTC epoch microseconds. Absolute reference. Subject to NTP steps; use monotonic for ordering."
    },
    "monotonic": {
      "type": "integer",
      "description": "Nanoseconds from CLOCK_MONOTONIC. Authoritative for ordering and for any interval within a session. Not comparable across boots."
    },
    "value": {
      "type": [
        "number",
        "string",
        "boolean",
        "null"
      ],
      "description": "null means the signal is known but currently has no value."
    },
    "unit": {
      "type": "string",
      "description": "Derived from signals.json. Never authored per message."
    },
    "quality": {
      "enum": [
        "ok",
        "stale",
        "invalid"
      ],
      "default": "ok",
      "description": "Omitted when ok."
    },
    "mock": {
      "type": "boolean",
      "default": false,
      "description": "Present and true when synthesised. Must be rendered visibly by any display."
    }
  }
}