{
  "example_version": "HRC-SIGNED-LIVE-PACKET-CONTRACT-v0.3.1",
  "runtime": "HRC_Heart-rate Resonance Control",
  "ko": "심박 공명 제어 시스템",
  "signature": {
    "algorithm": "HMAC-SHA256",
    "secret": "tenant license key",
    "canonicalization": "JSON canonical form with sort_keys=true and compact separators",
    "signed_payload": "entire packet except integrity.signature",
    "required_integrity_fields": [
      "device_id",
      "timestamp",
      "nonce",
      "session_id",
      "signature_alg",
      "signature"
    ]
  },
  "packet": {
    "source_type": "LIVE_DEVICE",
    "interval_ms": 250,
    "bio_phase_rad": 1.0,
    "stimulus_phase_rad": 0.92,
    "heart_rate_bpm": 68.4,
    "hrv_rmssd_ms": 39.2,
    "respiration_phase_rad": 1.0,
    "quality_score": 0.93,
    "actuator_latency_ms": 20,
    "integrity": {
      "device_id": "partner-device-001",
      "timestamp": "2026-05-16T00:00:00Z",
      "nonce": "unique-per-packet",
      "session_id": "hrc_session_id_from_start",
      "signature_alg": "HMAC-SHA256",
      "signature": "hex_hmac_sha256"
    }
  }
}