{
  "description": "SAR v0.1 FAIL fixture (controlled mismatch test vector)",
  "sar_version": "0.1",
  "input": {
    "task_id_hash": "sha256:fixture-task-001",
    "verdict": "FAIL",
    "confidence": 1,
    "reason_code": "SPEC_MISMATCH",
    "ts": "2026-02-14T12:00:00Z",
    "verifier_kid": "sar-prod-ed25519-01"
  },
  "canonical_json": "{\"confidence\":1,\"reason_code\":\"SPEC_MISMATCH\",\"task_id_hash\":\"sha256:fixture-task-001\",\"ts\":\"2026-02-14T12:00:00Z\",\"verdict\":\"FAIL\",\"verifier_kid\":\"sar-prod-ed25519-01\"}",
  "receipt_id": "sha256:aaf1ac2a88b53e9a5246a8c64b5b75f03a838ca38dedf6f39b17ac77a73cb6f6",
  "public_key_url": "https://defaultverifier.com/.well-known/sar-keys.json",
  "public_key_kid": "sar-prod-ed25519-01",
  "sig": "base64url:fbRXjoGDlaKGy-BwVkhYhJ3bkQpPQ3xbrkIN9r8oON-kyvE0MoWIjGu48pq1lVNaq2ZQ0WRHyQme_jY0-0h6CA",
  "verification_steps": [
    "1. JCS-canonicalize `input` (RFC 8785).",
    "2. Confirm it matches `canonical_json` byte-for-byte.",
    "3. SHA256(canonical_json bytes) => receipt_id hex.",
    "4. Verify Ed25519 signature over the hash bytes using public key from sar-keys.json."
  ]
}