EVM Smart Accounts

Prepare user operation

Changed on Oct 6, 2026

Prepares a new user operation on a Smart Account for a specific network.

post/v2/evm/smart-accounts/{address}/user-operations

Request

Base URL: https://api.cdp.coinbase.com/platform
URL: https://api.cdp.coinbase.com/platform/v2/evm/smart-accounts/{address}/user-operations
Auth: HTTP bearer

Path parameters

addressstring required

The address of the Smart Account to create the user operation on.

Request body

The network the user operation is for.

paymasterUrlstring uri

A valid HTTP or HTTPS URL.

paymasterContextPaymasterContext

The ERC-7677 context object forwarded to the paymaster service as part of the paymasterService capability. The fields in this object are defined by the paymaster service provider; CDP forwards them to the paymaster unchanged. This field is only valid when a paymaster is configured for the request. Providing paymasterContext without a paymaster configured results in an invalid_request error.

dataSuffixstring

The EIP-8021 data suffix (hex-encoded) that enables transaction attribution for the user operation.

Example request

{
  "network": "base",
  "calls": [
    {
      "to": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
      "value": "0",
      "data": "0xa9059cbb000000000000000000000000fc807d1be4997e5c7b33e4d8d57e60c5b0f02b1a0000000000000000000000000000000000000000000000000000000000000064",
      "overrideGasLimit": "100000"
    }
  ],
  "paymasterUrl": "https://example.com",
  "paymasterContext": {
    "policyId": "962b252c-a726-4a37-8d86-333ce0a07299"
  },
  "dataSuffix": "0xdddddddd62617365617070070080218021802180218021802180218021"
}

Response

The prepared user operation.

The network the user operation is for.

userOpHashstring required

The hash of the user operation. This is not the transaction hash, as a transaction consists of multiple user operations. The user operation hash is the hash of this particular user operation which gets signed by the owner of the Smart Account.

The status of the user operation.

transactionHashstring

The hash of the transaction that included this particular user operation. This gets set after the user operation is broadcasted and the transaction is included in a block.

expiresAtstring date-time

The timestamp at which the prepared user operation expires.

Example response

{
  "network": "base",
  "userOpHash": "0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef",
  "calls": [
    {
      "to": "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
      "value": "0",
      "data": "0xa9059cbb000000000000000000000000fc807d1be4997e5c7b33e4d8d57e60c5b0f02b1a0000000000000000000000000000000000000000000000000000000000000064"
    },
    {
      "to": "0xdac17f958d2ee523a2206206994597c13d831ec7",
      "value": "1000000000000000",
      "data": "0x"
    }
  ],
  "status": "pending",
  "transactionHash": "0x0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef",
  "receipts": [
    {
      "revert": {
        "data": "0x123",
        "message": "reason for failure"
      },
      "blockHash": "0x386544b58930c0ec9e8f3ed09fb4cdb76b9ae0a1a37ddcacebe3925b57978e65",
      "blockNumber": 29338819,
      "gasUsed": "100000"
    }
  ],
  "expiresAt": "2025-03-25T12:00:00Z"
}

Changes

Oct 6, 2026156440e9f8df Revision changes
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new incompatible_event_types enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_headers enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new invalid_webhook_url enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_action_pending enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_canceled enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_expired enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_invalid_status enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_policy_violation enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new mandate_revoked enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
- warning
  added the new subscription_limit_exceeded enum value to the response property for the response status
Sep 25, 2026229ed860a74b Revision changes
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new mfa_challenge_not_found enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status
- warning
  added the new operation_in_progress enum value to the response property for the response status

Operation history (19 revisions)