Create a transfer attestation for transferring tokens

curl --request POST \
  --url https://gateway-api-testnet.circle.com/v1/transfer \
  --header 'Content-Type: application/json' \
  --data '
[
  {
    "burnIntent": {
      "maxBlockHeight": "1000000000000000000",
      "maxFee": "1000000000000000000",
      "spec": {
        "version": 1,
        "sourceDomain": 0,
        "destinationDomain": 4,
        "sourceContract": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationContract": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceToken": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationToken": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceDepositor": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationRecipient": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceSigner": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationCaller": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "value": "1000000000000000000",
        "salt": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "hookData": "0x1a2b3c4d"
      }
    },
    "signature": "<string>"
  }
]
'

{
  "transferId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "attestation": "<string>",
  "signature": "<string>",
  "fees": {
    "total": "1.178",
    "token": "USDC",
    "perIntent": [
      {
        "transferSpecHash": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "domain": 0,
        "baseFee": "2",
        "transferFee": "0.125"
      }
    ]
  },
  "expirationBlock": "<string>"
}

POST

transfer

curl --request POST \
  --url https://gateway-api-testnet.circle.com/v1/transfer \
  --header 'Content-Type: application/json' \
  --data '
[
  {
    "burnIntent": {
      "maxBlockHeight": "1000000000000000000",
      "maxFee": "1000000000000000000",
      "spec": {
        "version": 1,
        "sourceDomain": 0,
        "destinationDomain": 4,
        "sourceContract": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationContract": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceToken": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationToken": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceDepositor": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationRecipient": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "sourceSigner": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "destinationCaller": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "value": "1000000000000000000",
        "salt": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "hookData": "0x1a2b3c4d"
      }
    },
    "signature": "<string>"
  }
]
'

{
  "transferId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "attestation": "<string>",
  "signature": "<string>",
  "fees": {
    "total": "1.178",
    "token": "USDC",
    "perIntent": [
      {
        "transferSpecHash": "0x1234567890123456789012345678901234567890123456789012345678901234",
        "domain": 0,
        "baseFee": "2",
        "transferFee": "0.125"
      }
    ]
  },
  "expirationBlock": "<string>"
}

Query Parameters

maxAttestationSize

integer

Maximum allowed size (in bytes) for the encoded attestation. If the attestation exceeds this size, the request will be rejected with a 400 error.

Required range: x >= 1

Body

application/json

Minimum array length: 1

Option 1
Option 2

burnIntent

object

required

Show child attributes

burnIntent.maxBlockHeight

string

required

The maximum block height at which this burn is valid.

Example:

"1000000000000000000"

burnIntent.maxFee

string

required

The maximum fee the user is willing to pay.

Example:

"1000000000000000000"

burnIntent.spec

object

required

Show child attributes

burnIntent.spec.version

integer

required

Version of the transfer spec (uint32).

Required range: 0 <= x <= 4294967295

Example:

1

burnIntent.spec.sourceDomain

integer

required

The domain of the wallet contract this transfer came from (uint32).

Required range: 0 <= x <= 4294967295

Example:

0

burnIntent.spec.destinationDomain

integer

required

The domain of the minter contract this transfer is valid for (uint32).

Required range: 0 <= x <= 4294967295

Example:

4

burnIntent.spec.sourceContract

string

required

The address of the wallet contract on the source domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.destinationContract

string

required

The address of the minter contract on the destination domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.sourceToken

string

required

The token address on the source domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.destinationToken

string

required

The token address on the destination domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.sourceDepositor

string

required

The address to debit within the wallet contract on the source domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.destinationRecipient

string

required

The address that should receive the funds on the destination domain (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.sourceSigner

string

required

The signer who signed for the transfer (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.destinationCaller

string

required

The address of the caller who may use the attestation, 0 address if any caller (32-byte padded).

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.value

string

required

The amount to be transferred.

Example:

"1000000000000000000"

burnIntent.spec.salt

string

required

An arbitrary value chosen by the user to be unique.

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

burnIntent.spec.hookData

string

Arbitrary bytes that may be used for onchain composition (optional).

Example:

"0x1a2b3c4d"

signature

string

required

The signature over the burnIntent.

Response

Successfully created transfer attestation or attestation set

Response containing a transfer attestation or attestation set and operator signature

transferId

string<uuid>

required

The unique identifier of the transfer.

attestation

string

required

The byte-encoded transfer attestation or attestation set that should be passed to the minter contract

signature

string

required

The signature of the operator on the byte-encoded transfer attestation or attestation set

fees

object

required

Information on the transfer fees to be charged.

Show child attributes

fees.total

string

required

Total fees from all burn intents across chains.

Example:

"1.178"

fees.token

enum<string>

required

Token symbol.

Available options:

USDC

Example:

"USDC"

fees.perIntent

object[]

required

List of fee breakdowns for each burn intent.

Show child attributes

fees.perIntent.transferSpecHash

string

required

Keccak256 hash of the encoded transfer specification.

Example:

"0x1234567890123456789012345678901234567890123456789012345678901234"

fees.perIntent.domain

enum<integer>

required

The domain ID of the chain where the burn intent originated (uint32).

Available options:

0,

1,

2,

3,

6,

7,

10

fees.perIntent.baseFee

string

required

Fixed gas fee charged for the burn transaction.

Example:

"2"

fees.perIntent.transferFee

string

Variable fee based on transfer amount. Omitted for same-chain burns.

Example:

"0.125"

expirationBlock

string

required

The block number on the destination chain after which this attestation expires.

Get Gateway info for supported domains and tokens

Get full TransferSpec by transferSpecHash