Who it is for

Agents that deliver something after a payment.

• Verify a payment before delivering
• Audit movements

How an agent buys it

POST https://a-upgradenet.com/x402/base-tx
Content-Type: application/json

{
  "hash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}

1) Answers 402 with the price (PAYMENT-REQUIRED)
2) The agent signs the payment (EIP-3009, USDC on Base) and repeats with PAYMENT-SIGNATURE
3) Receives the result + PAYMENT-RESPONSE

Example response

{
  "status": "completed",
  "chain": "base",
  "hash": "0x…",
  "found": true,
  "tx_status": "success",
  "block_number": "21000000",
  "from": "0x…",
  "to": "0x…",
  "value_eth": "0",
  "fee_eth": "0.0000012",
  "gas_used": "65000",
  "erc20_transfers": [
    {
      "token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "from": "0x…",
      "to": "0x…",
      "raw": "100000"
    }
  ]
}