Obolpay x402 Gateway

[
  {
    "error": "payment_required",
    "status": "payment_required",
    "accepts": [
      {
        "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
        "extra": {
          "name": "USD Coin",
          "version": "2",
          "invoice_id": "7d701052-0d81-4091-9cd7-79142bd175a1",
          "signature_header": "X-Payment-Signature",
          "signature_message_template": "x402:{domain}:{invoice_id}:{tx_hash}"
        },
        "payTo": "0x0d444D405dC168f29D66891383aa3542F5030057",
        "scheme": "exact",
        "network": "base",
        "mimeType": "application/json",
        "resource": "https://x402.obolpay.xyz/api/v1/protected-data",
        "description": "Verifiable data feed for AI agents: openunit (population-weighted unit of account at today's ECB FX, byte-for-byte reproducible), JP-equity KCS convergence scan, LLM-backend equivalence matrix, AI provenance/trust artifact pack, and governed-AI spending benchmarks. Multi-category (?types=), delta delivery, signed receipts, free preview.",
        "maxAmountRequired": "10000",
        "maxTimeoutSeconds": 300
      }
    ],
    "message": "支払いが必要です。payment情報に従い標準的なUSDC transferで送金し、X-Payment-Tx-Hash / X-Payment-Invoice-ID / X-Payment-Signature を提出してください。",
    "payment": {
      "token": "USDC",
      "amount": 0.01,
      "network": "base-mainnet",
      "preview": {
        "note": "Free preview. Pay the quoted USDC to unlock the full dataset.",
        "product": "Obolpay Verifiable Data Feed — openunit index + LLM-equivalence + governance benchmarks",
        "available": true,
        "feed_type": "append-only",
        "freshness": {
          "scheme": "EIP-191",
          "signer": "0xd50C176074fb94ED057f031C3Ebb6e2575433CA2",
          "verify": "Recover the EIP-191 signer from (message, signature); must equal `signer`. Verify freely via POST /verify-receipt. content_sha256 also lets you confirm the delivered data is unchanged and its stated age.",
          "message": "x402-freshness|x402.obolpay.xyz|c88d7a03ef54de8b14dabae59f291b3b6b1afaa55afe2224571008d718f7f43f|2026-07-22T11:57:01Z|2026-07-22T11:59:00Z",
          "signature": "0xab72bbf787a0770af02ea09419f1f7ffe8032339a1302b72f07ee109d20463db76874760177f846d6c54e72d939bf10da079cff28f81b4a42ca44c3a9eec7b4d1b",
          "age_seconds": 119,
          "attested_at": "2026-07-22T11:59:00Z",
          "generated_at": "2026-07-22T11:57:01Z",
          "content_sha256": "c88d7a03ef54de8b14dabae59f291b3b6b1afaa55afe2224571008d718f7f43f"
        },
        "item_count": 5,
        "latest_seq": 5,
        "sample_item": {
          "type": "llm-equivalence",
          "title": "Local-LLM backend equivalence & consistency matrix (Apple Silicon)",
          "description": "Measured cross-backend output agreement, consistency, swap latency, memory and t",
          "measured_at": "2026-06-06"
        },
        "schema_version": "1.1"
      },
      "chain_id": 8453,
      "recipient": "0x0d444D405dC168f29D66891383aa3542F5030057",
      "expires_at": "2026-07-22T12:04:00Z",
      "invoice_id": "7d701052-0d81-4091-9cd7-79142bd175a1",
      "prepaid_hint": "For frequent use, deposit once via POST /account/topup and then pay GASLESS with X-Account-* vouchers (no on-chain tx per call). See /.well-known/x402 -> prepaid_balance.",
      "invoice_status": "pending",
      "token_contract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "signature_scheme": {
        "note": "署名者はトランザクションの from（送金実行者）と一致している必要があります。domain はこのサーバーが署名検証に用いる値です。",
        "type": "EIP-191 (personal_sign)",
        "domain": "x402.obolpay.xyz",
        "header": "X-Payment-Signature",
        "example": "x402:x402.obolpay.xyz:7d701052-0d81-4091-9cd7-79142bd175a1:0x<tx_hash>",
        "message_template": "x402:{domain}:{invoice_id}:{tx_hash}"
      }
    },
    "retryable": false,
    "x402Version": 1
  }
]