{
  "contract": "horizon-shield-verification-contract",
  "version": "0.1.1",
  "issuer": {
    "organization": "The HORIZ音s株式会社",
    "service": "HORIZON SHIELD KIRA",
    "url": "https://shield.the-horizons-innovation.com"
  },
  "trust_model": "Conferred, not assumed. Any agent recomputes the claim itself from the response. No trust in the UI or the issuer is required.",
  "verified_result": {
    "description": "Fields present in every estimate-integrity-audit response that let a third party verify the claim without contacting the issuer.",
    "claim_hash": {
      "field": "claim_sha256",
      "algorithm": "SHA-256",
      "source_field": "signed_payload",
      "note": "signed_payload contains skill, input_text, red_flags, issued_at, expires_at, estimate_version. It does not contain souba-db prices. expires_at is issued_at plus 365 days. estimate_version is the first 8 hex of SHA-256 of input_text."
    },
    "recompute": "SHA-256(signed_payload) must equal claim_sha256. No price layer needed.",
    "estimator": {
      "id": "HORIZON SHIELD KIRA",
      "version": "1.0.0"
    },
    "ruleset": {
      "id": "kira-redflag",
      "version": "1",
      "note": "Only the ruleset identity is public. The souba-db thresholds behind it are not exposed."
    },
    "timestamp_anchor": {
      "type": "PTKA",
      "chain": "bitcoin",
      "block": 949356,
      "method": "OpenTimestamps",
      "per_diagnosis_roadmap": "Individual on-chain receipts per diagnosis are roadmapped via JIDEC."
    }
  },
  "failure_model": {
    "policy": "Fail closed. If the claim cannot be recomputed or the chain cannot be verified, the result is unverified. Never a soft pass.",
    "result_on_failure": "unverified",
    "failure_reasons": {
      "stale_data": {
        "user_meaning": "recheck later",
        "triggers": [
          "expired_declaration"
        ]
      },
      "changed_scope": {
        "user_meaning": "re-audit required",
        "triggers": [
          "changed_estimate_version"
        ]
      },
      "missing_evidence": {
        "user_meaning": "do not trust",
        "triggers": [
          "missing_receipt",
          "unverifiable_chain"
        ]
      }
    }
  },
  "credits": "Failure-reason taxonomy (stale data / changed scope / missing evidence) proposed by Symon Baikov (@symonbaikov.bsky.social).",
  "url": "https://hs-mcp.oga-surf-project.workers.dev/.well-known/verification-contract.json"
}