Approve Transaction

curl --request POST \
  --url https://staging.crossmint.com/api/2025-06-09/wallets/{walletLocator}/transactions/{transactionId}/approvals \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <x-api-key>' \
  --data '
{
  "approvals": [
    {
      "signer": "external-wallet:0x1234...",
      "signature": "0x1234567890abcdef..."
    }
  ]
}
'

{
  "chainType": "evm",
  "walletType": "smart",
  "params": {
    "calls": [
      {
        "address": "<string>",
        "functionName": "<string>",
        "abi": [
          "<unknown>"
        ],
        "args": [
          "<unknown>"
        ],
        "value": "0"
      }
    ],
    "chain": "abstract",
    "signer": {
      "type": "external-wallet",
      "address": "<string>",
      "locator": "<string>"
    }
  },
  "onChain": {
    "userOperation": {
      "sender": "<string>",
      "nonce": "<string>",
      "callData": "<string>",
      "callGasLimit": "<string>",
      "verificationGasLimit": "<string>",
      "preVerificationGas": "<string>",
      "maxFeePerGas": "<string>",
      "maxPriorityFeePerGas": "<string>",
      "signature": "<string>",
      "paymaster": "<string>",
      "paymasterVerificationGasLimit": "<string>",
      "paymasterData": "<string>",
      "paymasterPostOpGasLimit": "<string>",
      "factory": "<string>",
      "factoryData": "<string>"
    },
    "userOperationHash": "<string>",
    "txId": "<string>",
    "explorerLink": "<string>"
  },
  "id": "<string>",
  "status": "awaiting-approval",
  "createdAt": "2024-01-01T00:00:00.000Z",
  "approvals": {
    "pending": [
      {
        "signer": {
          "type": "external-wallet",
          "address": "<string>",
          "locator": "<string>"
        },
        "message": "<string>"
      }
    ],
    "submitted": [
      {
        "signature": "<string>",
        "submittedAt": "2024-01-01T00:00:00.000Z",
        "signer": {
          "type": "external-wallet",
          "address": "<string>",
          "locator": "<string>"
        },
        "message": "<string>",
        "metadata": {
          "deviceInfo": "<string>",
          "ipAddress": "<string>",
          "userAgent": "<string>"
        }
      }
    ],
    "required": 123
  },
  "completedAt": "2024-01-01T00:00:00.000Z",
  "error": {
    "reason": "build_failed",
    "message": "<string>"
  },
  "sendParams": {
    "token": "<string>",
    "params": {
      "recipient": "<string>",
      "recipientAddress": "<string>",
      "amount": "<string>"
    }
  }
}

POST

2025-06-09

wallets

{walletLocator}

transactions

{transactionId}

approvals

Approve Transaction

curl --request POST \
  --url https://staging.crossmint.com/api/2025-06-09/wallets/{walletLocator}/transactions/{transactionId}/approvals \
  --header 'Content-Type: application/json' \
  --header 'X-API-KEY: <x-api-key>' \
  --data '
{
  "approvals": [
    {
      "signer": "external-wallet:0x1234...",
      "signature": "0x1234567890abcdef..."
    }
  ]
}
'

{
  "chainType": "evm",
  "walletType": "smart",
  "params": {
    "calls": [
      {
        "address": "<string>",
        "functionName": "<string>",
        "abi": [
          "<unknown>"
        ],
        "args": [
          "<unknown>"
        ],
        "value": "0"
      }
    ],
    "chain": "abstract",
    "signer": {
      "type": "external-wallet",
      "address": "<string>",
      "locator": "<string>"
    }
  },
  "onChain": {
    "userOperation": {
      "sender": "<string>",
      "nonce": "<string>",
      "callData": "<string>",
      "callGasLimit": "<string>",
      "verificationGasLimit": "<string>",
      "preVerificationGas": "<string>",
      "maxFeePerGas": "<string>",
      "maxPriorityFeePerGas": "<string>",
      "signature": "<string>",
      "paymaster": "<string>",
      "paymasterVerificationGasLimit": "<string>",
      "paymasterData": "<string>",
      "paymasterPostOpGasLimit": "<string>",
      "factory": "<string>",
      "factoryData": "<string>"
    },
    "userOperationHash": "<string>",
    "txId": "<string>",
    "explorerLink": "<string>"
  },
  "id": "<string>",
  "status": "awaiting-approval",
  "createdAt": "2024-01-01T00:00:00.000Z",
  "approvals": {
    "pending": [
      {
        "signer": {
          "type": "external-wallet",
          "address": "<string>",
          "locator": "<string>"
        },
        "message": "<string>"
      }
    ],
    "submitted": [
      {
        "signature": "<string>",
        "submittedAt": "2024-01-01T00:00:00.000Z",
        "signer": {
          "type": "external-wallet",
          "address": "<string>",
          "locator": "<string>"
        },
        "message": "<string>",
        "metadata": {
          "deviceInfo": "<string>",
          "ipAddress": "<string>",
          "userAgent": "<string>"
        }
      }
    ],
    "required": 123
  },
  "completedAt": "2024-01-01T00:00:00.000Z",
  "error": {
    "reason": "build_failed",
    "message": "<string>"
  },
  "sendParams": {
    "token": "<string>",
    "params": {
      "recipient": "<string>",
      "recipientAddress": "<string>",
      "amount": "<string>"
    }
  }
}

Headers

X-API-KEY

string

required

API key required for authentication

Path Parameters

walletLocator

string

required

A wallet locator can be of the format:

<walletAddress>
email:<email>:<chainType>[:<walletType>][:alias:<alias>] (walletType defaults to 'smart')
userId:<userId>:<chainType>[:<walletType>][:alias:<alias>] (white label user example)
phoneNumber:<phoneNumber>:<chainType>[:<walletType>][:alias:<alias>]
twitter:<handle>:<chainType>[:<walletType>][:alias:<alias>]
x:<handle>:<chainType>[:<walletType>][:alias:<alias>]
me:<chainType>[:<walletType>][:alias:<alias>] (Use when calling from the client side with a client API key)
chainType[:<walletType>]:alias:<alias>

transactionId

string

required

Body

application/json

Input for submitting one or more approvals

approvals

(Passkey signature submission payload · object | External wallet signature submission payload · object | Email signer signature submission payload · object | Phone signer signature submission payload · object | Device signer signature submission payload · object)[]

required

Array of approvals to submit for this transaction

Minimum array length: 1

Schema for WebAuthn signature data

Passkey signature submission payload
External wallet signature submission payload
Email signer signature submission payload
Phone signer signature submission payload
Device signer signature submission payload

Show child attributes

approvals.signer

string

required

The locator for the passkey signer

Example:

"passkey:-y--aq1hqKC_ipuPHa-8aQ"

approvals.signature

object

required

The signature components

Show child attributes

approvals.signature.r

string

required

R component of the signature as a stringified bigint

approvals.signature.s

string

required

S component of the signature as a stringified bigint

approvals.metadata

object

required

WebAuthn signature metadata

Show child attributes

approvals.metadata.authenticatorData

string

required

WebAuthn authenticator data as hex string

approvals.metadata.challengeIndex

number

required

Index of the challenge used

approvals.metadata.clientDataJSON

string

required

WebAuthn client data JSON string

approvals.metadata.typeIndex

number

required

Index of the signature type

approvals.metadata.userVerificationRequired

boolean

required

Whether user verification was required

Response

The approval has successfully been submitted to the transaction.

EVM Smart Wallet
EVM MPC Wallet
Solana Smart Wallet
Solana MPC Wallet
Stellar Smart Wallet

Complete transaction response including status, signing requirements, and wallet type specific data

chainType

enum<string>

required

The blockchain type of the wallet

Available options:

evm,

solana,

aptos,

sui,

stellar

walletType

enum<string>

required

The wallet type (smart or mpc)

Available options:

smart,

mpc

params

object

required

Show child attributes

params.calls

(EVM contract call transaction parameters · object | EVM direct calldata transaction parameters · object | EVM serialized transaction parameters · object)[]

required

Array of transaction calls to execute

Minimum array length: 1

Transaction data to execute

EVM contract call transaction parameters
EVM direct calldata transaction parameters
EVM serialized transaction parameters

Show child attributes

params.calls.address

string

required

The recipient address for this transaction call

params.calls.functionName

string

required

The name of the function to call

params.calls.abi

any[]

required

The ABI for the function to call

params.calls.args

any[]

required

The arguments to pass to the function

params.calls.value

string

default:0

The amount of native token to send in wei

params.chain

enum<string>

required

The chain on which the transaction will be executed

Available options:

abstract,

apechain,

arbitrum,

arbitrumnova,

avalanche,

base,

bsc,

flow,

mantle,

mode,

optimism,

plume,

polygon,

scroll,

sei-pacific-1,

shape,

story,

world-chain,

zora,

abstract-testnet,

arbitrum-sepolia,

avalanche-fuji,

base-sepolia,

curtis,

ethereum-sepolia,

flow-testnet,

mantle-sepolia,

mode-sepolia,

optimism-sepolia,

plume-testnet,

polygon-amoy,

scroll-sepolia,

sei-atlantic-2-testnet,

story-testnet,

world-chain-sepolia,

zora-sepolia,

arc-testnet

params.signer

External Wallet Signer · object

The full signer object who will submit this transaction

External Wallet Signer
Passkey Signer
API Key Signer
Device Signer
Option 5
Option 6

Show child attributes

params.signer.type

enum<string>

required

Available options:

external-wallet

params.signer.address

string

required

The address of the external wallet

params.signer.locator

string

required

The locator of the external wallet signer

onChain

EVM smart wallet transaction data · object

required

Transaction data specific to EVM smart wallets

Show child attributes

onChain.userOperation

object

required

Show child attributes

onChain.userOperation.sender

string

required

onChain.userOperation.nonce

string

required

onChain.userOperation.callData

string

required

onChain.userOperation.callGasLimit

string

required

onChain.userOperation.verificationGasLimit

string

required

onChain.userOperation.preVerificationGas

string

required

onChain.userOperation.maxFeePerGas

string

required

onChain.userOperation.maxPriorityFeePerGas

string

required

onChain.userOperation.signature

string

required

onChain.userOperation.paymaster

string

onChain.userOperation.paymasterVerificationGasLimit

string

onChain.userOperation.paymasterData

string

onChain.userOperation.paymasterPostOpGasLimit

string

onChain.userOperation.factory

string

onChain.userOperation.factoryData

string

onChain.userOperationHash

string

required

onChain.txId

string

onChain.explorerLink

string

required

Unique identifier for the transaction

status

enum<string>

required

Current status of the transaction

Available options:

awaiting-approval,

pending,

failed,

success

createdAt

required

ISO timestamp when the transaction was created

Example:

"2024-01-01T00:00:00.000Z"

approvals

object

Complete approval data including requirements, pending and submitted signatures

Show child attributes

approvals.pending

object[]

required

List of pending signatures

Show child attributes

approvals.pending.signer

External Wallet Signer · object

required

The full signer object that's pending approval

External Wallet Signer
Passkey Signer
API Key Signer
Device Signer
Option 5
Option 6

Show child attributes

approvals.pending.signer.type

enum<string>

required

Available options:

external-wallet

approvals.pending.signer.address

string

required

The address of the external wallet

approvals.pending.signer.locator

string

required

The locator of the external wallet signer

approvals.pending.message

string

required

The message that needs to be signed

approvals.submitted

object[]

required

Record of all submitted signatures

Show child attributes

approvals.submitted.signature

string

required

The cryptographic signature

approvals.submitted.submittedAt

required

When the signature was submitted

Example:

"2024-01-01T00:00:00.000Z"

approvals.submitted.signer

External Wallet Signer · object

required

The full signer object who submitted this signature

External Wallet Signer
Passkey Signer
API Key Signer
Device Signer
Option 5
Option 6

Show child attributes

approvals.submitted.signer.type

enum<string>

required

Available options:

external-wallet

approvals.submitted.signer.address

string

required

The address of the external wallet

approvals.submitted.signer.locator

string

required

The locator of the external wallet signer

approvals.submitted.message

string

required

The message that was signed

approvals.submitted.metadata

object

Additional metadata about the signature submission

Show child attributes

approvals.submitted.metadata.deviceInfo

string

approvals.submitted.metadata.ipAddress

string

approvals.submitted.metadata.userAgent

string

approvals.required

number

Number of required approvals for the transaction

completedAt

ISO timestamp when the transaction reached finality

Example:

"2024-01-01T00:00:00.000Z"

error

object

Error message if the transaction fails after submission

Option 1
Option 2
Option 3

Show child attributes

error.reason

enum<string>

required

Available options:

build_failed,

failed_to_land_on_chain,

unknown,

sanctioned_wallet_address

error.message

string

required

sendParams

object

Show child attributes

sendParams.token

string

required

The token locator that's being sent

sendParams.params

object

required

The parameters for the send token transaction

Show child attributes

sendParams.params.recipient

string

required

The recipient locator for the token

sendParams.params.recipientAddress

string

required

The recipient address for the token

sendParams.params.amount

string

The amount of the token to send

Get Wallet Transactions Create Signature

Introduction

Quickstarts ⚡️

Concepts

Guides

API Reference

Approve Transaction

Headers

Path Parameters

Body

Response