Token Approval

POST /approve

This endpoint generates an unsigned transaction for approving token spending. The approval transaction lets a smart contract (or a specified sender address) spend a given amount of tokens on behalf of the recipient. If a sender is provided, the approval will be generated using that address (and only the ENSC asset type is allowed in that case). Otherwise, the recipient’s address is used.

Headers

Name	Value
Content-Type	application/json
Authorization	Bearer <api_key>

Body

Name	Type	Description
recipient	string	The wallet address that will receive the approval.
assetType	string	The asset type, provided as an enum value (e.g., ENSC, USDC, USDT, etc.).
amount	number	The amount to approve.
sender	string	Optional. If provided, the approval will be generated using this address instead of the recipient. When provided, only ENSC is allowed as the asset type.

Example 1: Approval for Redeeming Assets (No Sender Provided)

Request

Body

{
  "recipient": "0xRecipientAddressABC123",
  "assetType": "USDC",
  "amount": 50
}

Response (200) Ok

{
  "status": 200,
  "message": "Unsigned approve transaction generated successfully",
  "data": {
    "to": "0xTokenContractAddressXYZ",
    "value": 0,
    "gasLimit": "0x186a0",
    "gasPrice": "20000000000",
    "nonce": "5",
    "data": "0x095ea7b3000000000000000000000000DEXContractAddressDEF4560000000000000000000000000000000000000000000000000000000000000032",
    "from": "0xRecipientAddressABC123",
    "spender": "0xDEXContractAddressDEF456"
  }
}

Invalid Recipient (400) bad

{
  "status": 400,
  "error": "Invalid Request",
  "message": "Invalid recipient address",
  "data": null
}

Example 2: Approval for Transfers (Sender Provided)

Response

Body

{
  "recipient": "0xRecipientAddressABC123",
  "sender": "0xSenderAddress987654",
  "assetType": "ENSC",
  "amount": 10
}

Response (200) Ok

{
  "status": 200,
  "message": "Unsigned approve transaction generated successfully",
  "data": {
    "to": "0xTokenContractAddressXYZ",
    "value": 0,
    "gasLimit": "0x186a0",
    "gasPrice": "20000000000",
    "nonce": "12",
    "data": "0x095ea7b3000000000000000000000000SenderAddress987654000000000000000000000000000000000000000000000000000000000000000a",
    "from": "0xSenderAddress987654",
    "spender": "0xSenderAddress987654"
  }
}

Invalid Asset When Sender is Provided (400) bad

{
  "status": 400,
  "error": "Invalid Asset",
  "message": "When a sender is provided, only ENSC asset type is allowed",
  "data": null
}