{
  "reason": "A declared reading without its version is unreproducible: two auditors on two dates could not tell whether they read alike. All four keys are required when the object is present (SPEC §4.1).",
  "message": {
    "envelope": "1.1",
    "id": "temoin/EVI-999",
    "class": "measure",
    "subject": "x",
    "statement": "y",
    "evidence": [],
    "provenance": "measured",
    "confidence": 1.0,
    "endorsement": null,
    "jurisdiction": "temoin",
    "at": "2026-09-19T08:00:00Z",
    "lifecycle": "proposed",
    "relations": {},
    "deadline": null,
    "falsification": null,
    "confidence_reading": { "policy": "half-life-by-class", "value": 0.87, "as_of": "2026-09-19T08:00:00Z" }
  }
}