gpt55-x402-gateway

x402 Wallet Signing Safety Pack

Use this page when an agent, wallet UI, MCP tool, or Flowise node is about to sign typed data, approve a spender, send calldata, or pay an x402 quote and needs one allow/manual-review/deny packet before value moves.

Live Assets

• Product page: https://gpt55.558686.xyz/x402/wallet-signing-safety-pack
• Product JSON: https://gpt55.558686.xyz/x402/wallet-signing-safety-pack.json
• Paid endpoint: https://gpt55.558686.xyz/v1/paid/wallet-signing-safety-pack
• GitHub example: https://github.com/go165/gpt55-x402-gateway/tree/main/examples/wallet-signing-safety-pack
• Paid result shape: https://github.com/go165/gpt55-x402-gateway/blob/main/examples/wallet-signing-safety-pack/paid-result-shape.json
• Wallet first-purchase center: https://gpt55.558686.xyz/x402/wallet-prepay-first-purchase

Quote-only Check

node examples/wallet-signing-safety-pack/check-wallet-signing-safety-pack.mjs
ROUTE_ID=wallet-signing-safety-pack MAX_USDC=0.02 node first-payment-client.mjs

Quote-only mode does not use private keys, sign, pay, broadcast, register, or do KYC.

Expected quote:

• price: $0.018
• amount: 18000 atomic USDC
• network: eip155:8453
• payTo: 0x1f0130669ca6fd02e025a984cc038f139df19a2f

What The Paid Result Gives

After a real buyer-owned x402 payment, the paid JSON includes decision, riskLevel, riskFlags, paymentPolicyDecision, paymentPolicyInputs, agentEnforcementPayload, receiptEvidence, buyerActionChecklist, purchaseResultCard, and repeatPurchaseContract.

agentEnforcementPayload is the reusable part: copy it into MCP, Flowise, or wallet runtime guard examples before the next sign/pay action.

Buyer-owned Payment Path

git clone https://github.com/go165/gpt55-x402-gateway.git && cd gpt55-x402-gateway
npm install
npm run first-payment:root
ROUTE_ID=wallet-signing-safety-pack MAX_USDC=0.02 node first-payment-client.mjs
PAY_REAL_X402=1 ROUTE_ID=wallet-signing-safety-pack MAX_USDC=0.02 EVM_PRIVATE_KEY=0x... node first-payment-client.mjs

The service never receives a private key. The buyer client creates X-PAYMENT locally only after amount, network, payTo, and spend-cap checks pass.

Repeat Purchase Trigger

Buy again for new typed data, a new spender, a new Permit or Permit2 request, a new calldata approval, a new wallet runtime policy, or a changed x402 prepay policy.

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