Motiv

Submit transaction#

Submit the signed transaction to the blockchain for on-chain settlement.

Request address#

POST https://web3.okx.com/api/v6/x402/settle

Request parameters#

Request body

Parameter	Type	Required	Description
x402Version	String	Yes	Version of the x402 protocol. For v1, pass integer 1
chainIndex	String	Yes	Unique identifier of the blockchain
paymentPayload	Object	Yes	The x402 payment payload carried by the client with the protected request
>x402Version	String	Yes	Version of the x402 protocol. For v1, pass integer 1
>scheme	String	Yes	Settlement scheme defining how the payment is processed, e.g. exact (one‑time fixed‑amount payment)
>payload	Object	Yes	Object containing payment signature and authorization data
>>signature	String	Yes	Cryptographic signature
>>authorization	Object	Yes	Authorization information
>>>from	String	Yes	Payer address
>>>to	String	Yes	Payee address
>>>value	String	Yes	Payment amount in the smallest on-chain unit (e.g. for USDT with 6 decimals, 1 USDT = 1000000)
>>>validAfter	String	Yes	Unix timestamp (seconds) after which the authorization becomes valid
>>>validBefore	String	Yes	Unix timestamp (seconds) before which the authorization is valid (expiration)
>>>nonce	String	Yes	A 32-byte hex random nonce to prevent replay attacks
paymentRequirements	Object	Yes	Information describing what resource the payment grants access to (including amount, network, asset, and payee)
>scheme	String	Yes	Defines how the payment is settled, e.g. exact (one‑time fixed‑amount payment)
>resource	String	No	Server URL of the resource
>description	String	No	Description of the resource API endpoint
>mimeType	String	No	MIME type of the resource provider’s response
>maxAmountRequired	String	Yes	Maximum payable amount in the smallest on-chain unit (e.g. for USDT with 6 decimals, 1 USDT = 1000000)
>maxTimeoutSeconds	Integer	No	Maximum waiting time in seconds after the authorization becomes valid
>payTo	String	Yes	Payee address
>asset	String	No	Asset identifier or contract address (depending on the network)
>outputSchema	Object	No	Expected JSON structure of the returned resource data
>extra	Object	No	Additional parameters, e.g. gasLimit

Response parameter#

Parameter	Type	Description
chainIndex	String	Unique identifier of the blockchain, e.g. 196: X Layer
chainName	String	Name of the blockchain, e.g. X Layer
success	Boolean	Indicates whether the settlement was successful
payer	String	Address of the payer
txHash	String	Transaction hash of the settlement (EVM: 0x hash; Solana: Base58)
errorMsg	String	Error message, e.g. insufficient_funds, invalid_payload, etc

Verify the transaction

Error code

Request example#

Shell

curl --location --request POST 'https://web3.okx.com/api/v6/x402/settle' \
--header 'Content-Type: application/json' \
--header 'OK-ACCESS-KEY: <your-api-key>' \
--header 'OK-ACCESS-SIGN: <your-signature>' \
--header 'OK-ACCESS-PASSPHRASE: <your-passphrase>' \
--header 'OK-ACCESS-TIMESTAMP: <your-timestamp>' \
  --data '{
  "x402Version": 1,
  "chainIndex": 196,
  "paymentPayload": {
    "x402Version": 1,
    "scheme": "exact",
    "payload": {
      "signature": "<your-signature>",
      "authorization": {
        "from": "<payer-wallet-address>",
        "to": "<payee-wallet-address>",
        "value": "1000000",
        "validAfter": "<unix-timestamp-seconds>",
        "validBefore": "<unix-timestamp-seconds>",
        "nonce": "<your-nonce>"
      }
    }
  },
  "paymentRequirements": {
    "scheme": "exact",
    "maxAmountRequired": "0",
    "resource": "https://api.example.com/premium/resource/123",
    "description": "Premium API access for data analysis",
    "mimeType": "application/json",
    "outputSchema": {
      "data": "string"
    },
    "payTo": "<payee-wallet-address>",
    "maxTimeoutSeconds": 10,
    "asset": "<asset-contract-address>",
    "extra": {
      "gasLimit": "1000000"
    }
  }
}'

Response example#

Json

{
    "code": "0",
    "msg": "success",
    "data": [
        {
            "success": true,
            "errorReason": null,
            "payer": "<payer-wallet-address>",
            "txHash": "<transaction-hash>",
            "chainIndex": "196",
            "chainName": "X Layer"
        }
    ]
}

Verify the transaction

Error code