> ## Documentation Index
> Fetch the complete documentation index at: https://developers.circle.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Modular wallets iOS SDK

Welcome to Circle's modular wallets iOS SDK documentation. The SDK enables
developers to integrate modular wallets to build secure, scalable Web3
applications by leveraging tools for key management, smart account interactions,
gasless transactions, and blockchain communication.

## Installation

Follow the steps provided in the
[GitHub repository](https://github.com/circlefin/modularwallets-ios-sdk#installation)
to install and set up the modular wallets iOS SDK.

## API Documentation

The following sections detail the SDK's transport mechanisms, client
interactions, account management, utility functions, model structures, and
supported blockchain networks.

***

### Transports

#### Protocol: `Transport`

* **Description**: Interface representing a transport mechanism for making RPC
  requests.

##### Methods

###### `request`

* **Description**: Sends an RPC request and returns the response.
* **Parameters**:
  * `rpcRequest`: `RpcRequest` - The RPC request to be sent.
* **Returns**: `RpcResponse`

#### Class: `HttpTransport`

* **Description**: The `HttpTransport` confirms the protocol `Transport` and
  implements the required methods.

#### Class: `ModularTransport`

* **Description**: The `ModularTransport` inherits `HttpTransport` and confirms
  the protocol `ModularRpcApi`.

#### Structure: `HttpRpcClientOptions`

* **Description**: Data class representing HTTP RPC client options.
* **Properties**:
  * `headers`: `[String: String]` - Headers to include in the HTTP requests.

#### Function: `toModularTransport`

The `url` parameter takes the form `<modular wallets base URL>/<chain>`, where
`<chain>` is the `lowerCamelCase` form of a [Chain](#chains) protocol name (for
example, `ArcTestnet` maps to `arcTestnet`, `PolygonAmoy` maps to
`polygonAmoy`).

* **Description**: Creates an instance of `ModularTransport` with the provided
  client key and URL.
* **Parameters**:
  * `clientKey`: `String` - The client key for authorization.
  * `url`: `String` - The URL for the HTTP transport.
* **Returns**: `HttpTransport` - The configured HTTP transport instance.

#### Function: `toPasskeyTransport`

* **Description**: Creates an instance of `HttpTransport` with the provided
  client key and URL, setting the authorization header.
* **Parameters**:
  * `clientKey`: `String` - The client key for authorization.
  * `url`: `String` - The URL of the transport endpoint. Defaults to
    `CIRCLE_BASE_URL`.
* **Returns**: `HttpTransport` - The configured HTTP transport instance.

#### Function: `http`

* **Description**: Creates an HTTP transport instance.
* **Parameters**:
  * `url`: `String` - The URL for the HTTP transport.
  * `options`: `HttpRpcClientOptions?` - Optional configuration options for the
    HTTP transport.
* **Returns**: `HttpTransport` - The configured HTTP transport instance.

***

### Clients

#### Class: `Client`

* **Description**: Represents a client that interacts with a blockchain, with
  the following derived classes:
  * `BundlerClient`
  * `PaymasterClient`
* **Properties**:
  * `chain`: `Chain` - The blockchain that the client interacts with.
  * `transport`: `Transport` - The transport mechanism used for making RPC
    requests.

#### Class: `BundlerClient`

* **Description**: Client for interacting with the Bundler API. A
  `BundlerClient` is an interface to interact with ERC-4337 Bundlers and
  provides the ability to send and retrieve User Operations through Bundler
  Actions.
* **Inheritance**: Inherits from `Client`.

##### Methods

###### `estimateUserOperationGas`

* **Description**: Estimates the gas values for a User Operation to be executed
  successfully.
* **Parameters**:
  * `account`: `SmartAccount` - The smart account to use for User Operation
    execution.
  * `calls`: `[EncodeCallDataArg]` - The calls to execute in the User Operation.
  * `paymaster`: `Paymaster?` - Optional, sets Paymaster configuration for the
    User Operation.
  * `estimateFeesPerGas`:
    `((SmartAccount, BundlerClient, UserOperationV07) async -> EstimateFeesPerGasResult)?` -
    Optional, prepares fee properties for the User Operation request.
* **Returns**: `EstimateUserOperationGasResult` - The result of the gas
  estimation.

###### `getChainId`

* **Description**: Returns the chain ID associated with the current network.
* **Returns**: `Int` - The current chain ID.

###### `getSupportedEntryPoints`

* **Description**: Retrieves the EntryPoints that the bundler supports.
* **Returns**: `[String]` - A list of supported EntryPoints.

###### `getUserOperation`

* **Description**: Retrieves information about a User Operation given a hash.
* **Parameters**:
  * `userOpHash`: `String` - The hash of the User Operation.
* **Returns**: `GetUserOperationResult` - User Operation information.

###### `getUserOperationReceipt`

* **Description**: Returns the User Operation Receipt given a User Operation
  hash.
* **Parameters**:
  * `userOpHash`: `String` - The hash of the User Operation.
* **Returns**: `GetUserOperationReceiptResult` - The User Operation receipt.

###### `prepareUserOperation`

* **Description**: Prepares a User Operation for execution and fills in missing
  properties.
* **Parameters**:
  * `account`: `SmartAccount` - The smart account to use for User Operation
    execution.
  * `calls`: `[EncodeCallDataArg]?` - The calls to execute in the User
    Operation.
  * `partialUserOp`: `UserOperationV07` - The partial User Operation to be
    completed.
  * `paymaster`: `Paymaster?` - Optional, sets Paymaster configuration for the
    User Operation.
  * `estimateFeesPerGas`:
    `((SmartAccount, BundlerClient, UserOperationV07) async -> EstimateFeesPerGasResult)?` -
    Optional, prepares fee properties for the User Operation request.
* **Returns**: `UserOperationV07` - The prepared User Operation.

###### `sendUserOperation`

* **Description**: Sends a User Operation to the Bundler.
* **Parameters**:
  * `account`: `SmartAccount` - The smart account to use for User Operation
    execution.
  * `calls`: `[EncodeCallDataArg]?` - The calls to execute in the User
    Operation.
  * `partialUserOp`: `UserOperationV07` - The partial User Operation to be
    completed.
  * `paymaster`: `Paymaster?` - Optional, sets Paymaster configuration for the
    User Operation.
  * `estimateFeesPerGas`:
    `((SmartAccount, BundlerClient, UserOperationV07) async -> EstimateFeesPerGasResult)?` -
    Optional, prepares fee properties for the User Operation request.
* **Returns**: `String?` - Optional, the hash of the sent User Operation, or
  `null` otherwise.

###### `waitForUserOperationReceipt`

* **Description**: Waits for the User Operation to be included in a block (one
  confirmation) and then returns the User Operation receipt.
* **Parameters**:
  * `userOpHash`: `String` - The User Operation hash.
  * `pollingInterval`: `Int` (default: `4000`) - The polling interval in
    milliseconds.
  * `retryCount`: `Int` (default: `6`) - The number of retries.
  * `timeout`: `Int?` - Optional timeout in milliseconds to wait before stopping
    polling.
* **Returns**: `GetUserOperationReceiptResult` - The result of the User
  Operation receipt retrieval.

###### `getBalance`

* **Description**: Retrieves the balance of the specified address at a given
  block tag or block number.
* **Parameters**:
  * `address`: `String` - The address to query the balance for. Only wallet
    addresses registered with the client key can be retrieved.
  * `blockNumber`: `BlockNumber` - The block number (default: `.latest`).
* **Returns**: `BigInt` - The balance of the address.

###### `getBlockNumber`

* **Description**: Returns the number of the most recent block seen.
* **Returns**: `BigInt` - The current block number.

###### `getGasPrice`

* **Description**: Retrieves the current gas price (in wei).
* **Returns**: `BigInt` - The current gas price (in wei).

###### `call`

* **Description**: Executes a new message call immediately without submitting a
  transaction to the network.
* **Parameters**:
  * `from`: `String?` - Optional, the address to send the call from.
  * `to`: `String` - The contract address or recipient.
  * `data`: `Data` - A contract hashed method call with encoded arguments.
* **Returns**: `String` - The call data.

###### `getCode`

* **Description**: Retrieves the bytecode at an address.
* **Parameters**:
  * `address`: `String` - The contract address.
  * `blockNumber`: `BlockNumber` - The block number (default: `.latest`).
* **Returns**: `String` - The contract's bytecode.

###### `estimateMaxPriorityFeePerGas`

* **Description**: Returns an estimate for the max priority fee per gas (in wei)
  for a transaction to likely be included in the next block. The Action will
  either call `eth_maxPriorityFeePerGas` (if supported) or manually calculate
  the max priority fee per gas based on the current block base fee per gas + gas
  price.
* **Returns**: `BigInt` - An estimate (in wei) for the max priority fee per gas.

###### `getBlock`

* **Description**: Returns information about a block at a specific block number.
* **Parameters**:
  * `includeTransactions`: `Boolean` (default: `false`) - Whether or not to
    include transactions (as a structured array of `Transaction` objects).
  * `blockNumber`: `BlockNumber` - The block number (default: `.latest`).
* **Returns**: `Block` - The block information.

###### `getUserOperationGasPrice`

Available only for modular wallets.

* **Description**: Retrieves gas price options for a user operation. You may
  include the SDK version parameter.
* **Returns**: `GetUserOperationGasPriceResult` - The gas price options in each
  tier (low, medium, high) and `verificationGasLimit` (optional).

#### Class: `PaymasterClient`

* **Description**: Client for interacting with the Paymaster API. A
  `PaymasterClient` is an interface to interact with
  [ERC-7677 compliant Paymasters](https://eips.ethereum.org/EIPS/eip-7677) and
  provides the ability to sponsor User Operation gas fees.
* **Inheritance**: Inherits from `Client`.

##### Methods

###### `getPaymasterData`

* **Description**: Retrieves paymaster-related User Operation properties to be
  used for sending the User Operation.
* **Parameters**:
  * `userOp`: `T` - The User Operation to retrieve Paymaster data for. Type `T`
    must be a subclass of `UserOperation`.
  * `entryPoint`: `EntryPoint` - The EntryPoint address to target.
  * `context`: `[String: AnyEncodable]?` - Optional, paymaster-specific fields.
* **Returns**: `GetPaymasterDataResult` - Paymaster-related User Operation
  properties.

###### `getPaymasterStubData`

* **Description**: Retrieves paymaster-related User Operation properties to be
  used for gas estimation.
* **Parameters**:
  * `userOp`: `T` - The User Operation to retrieve Paymaster data for. Type `T`
    must be a subclass of `UserOperation`.
  * `entryPoint`: `EntryPoint` - The EntryPoint address to target.
  * `context`: `[String: AnyEncodable]?` - Optional, paymaster-specific fields.
* **Returns**: `GetPaymasterStubDataResult` - Paymaster-related User Operation
  properties.

***

### Accounts

#### Function: `toCircleSmartAccount`

* **Description**: Creates a Circle passkey account.
* **Parameters**:
  * `client`: `Client` - The client used to interact with the blockchain.
  * `owner`: `Account<SignResult>` - The owner account associated with the
    Circle Passkey account.
  * `version`: `String` (default: `"circle_passkey_account_v1"`) - The version
    of the Circle Passkey account.
  * `name`: `String?` (optional, defaults to the format
    `passkey-yyyy-MM-dd'T'HH:mm:ss.SSS'Z'`) - The wallet name assigned to the
    newly registered account.
* **Returns**: `CircleSmartAccount`

#### Function: `toWebAuthnAccount`

* **Description**: Creates a WebAuthn account.
* **Parameters**:
  * `credential`: `WebAuthnCredential` - The WebAuthn credential associated with
    the account.
* **Returns**: `WebAuthnAccount` - The created WebAuthn account.

#### Function: `toWebAuthnCredential`

* **Description**: Logs in or registers a user and returns a
  `WebAuthnCredential`.
* **Parameters**:
  * `transport`: `Transport` - The transport used to communicate with the RP
    API.
  * `userName`: `String?` (optional, required for `WebAuthnMode.Register`) - The
    username of the user.
  * `mode`: `WebAuthnMode` - The mode of the WebAuthn credential.
* **Returns**: `WebAuthnCredential`
* **Throws**: `BaseError` if `userName` is `null` for `WebAuthnMode.Register`.

#### Structure: `WebAuthnCredential`

* **Description**: Represents a P-256 WebAuthn credential used for registration
  and login.
* **Properties**:
  * `id`: `String` - The unique identifier for the credential.
  * `publicKey`: `String` (serialized hex) - The public key associated with the
    credential.
  * `raw`: `PublicKeyCredential` - The raw public key credential.
  * `rpId`: `String` - The relying party identifier.

#### Protocol: `Account`

* **Description**: A protocol defining the required methods for an account.
* **Type Parameter**: `T` - The type of the signed data.

##### Methods

###### `getAddress`

* **Description**: Retrieves the address of the account.
* **Returns**: `String` - The account's address.

###### `sign`

* **Description**: Signs the given hex data.
* **Parameters**:
  * `hex`: `String` - The hex data to sign.
* **Returns**: `T` - The signed data.

###### `signMessage`

* **Description**: Signs the given message.
* **Parameters**:
  * `message`: `String` - The message to sign.
* **Returns**: `T` - The signed message.

###### `signTypedData`

* **Description**: Signs the given typed data.
* **Parameters**:
  * `typedData`: `String` - The typed data to sign.
* **Returns**: `T` - The signed typed data.

#### Structure: `WebAuthnAccount`

* **Description**: Represents a WebAuthn account for handling authentication
  credentials and signing. Commonly used as a
  [Smart Account](https://viem.sh/account-abstraction/accounts/smart) owner to
  sign User Operations and messages on behalf of the Smart Account.
* **Conforms To**: `Account`

##### Methods

###### `getAddress`

* **Description**: Retrieves the public key address associated with the WebAuthn
  credential.
* **Returns**: `String` - The associated public key.

###### `sign`

* **Description**: Signs the given hex data.
* **Parameters**:
  * `hex`: `String` - The hex string to sign.
* **Returns**: `SignResult` - The result of the signing operation.

###### `signMessage`

* **Description**: Signs a message.
* **Parameters**:
  * `message`: `String` - The message to sign.
* **Returns**: `SignResult` - The result of the signing operation.

###### `signTypedData`

* **Description**: Signs typed data.
* **Parameters**:
  * `jsonData`: `String` - The JSON data to sign.
* **Returns**: `SignResult` - The result of the signing operation.

#### Protocol: `SmartAccount`

* **Description**: A Smart Account is an account whose implementation resides in
  a smart contract and implements the
  [ERC-4337 interface](https://eips.ethereum.org/EIPS/eip-4337#account-contract-interface).
* **Properties**:
  * `client`: `Client` - The client used to interact with the blockchain.
  * `entryPoint`: `EntryPoint` - The entry point for the smart account.
  * `userOperation`: `UserOperationConfiguration?` - Configuration for the User
    Operation.

##### Methods

###### `getAddress`

* **Description**: Returns the address of the account.
* **Returns**: `String` - The account address.

###### `encodeCalls`

* **Description**: Encodes the given call data arguments.
* **Parameters**:
  * `args`: `[EncodeCallDataArg]` - The call data arguments to encode.
* **Returns**: `String` - The encoded call data.

###### `getFactoryArgs`

* **Description**: Retrieves the factory arguments for the smart account.
* **Returns**: `(String, String)?` - A pair containing the factory address and
  factory data.

###### `getNonce`

* **Description**: Retrieves the nonce for the smart account.
* **Parameters**:
  * `key`: `BigInt?` - Optional key to retrieve the nonce for.
* **Returns**: `BigInt` - The nonce value.

###### `getStubSignature`

* **Description**: Retrieves the stub signature for a User Operation.
* **Parameters**:
  * `userOp`: `T` - The User Operation.
* **Returns**: `String` - The stub signature.

###### `sign`

* **Description**: Signs the given hex string.
* **Parameters**:
  * `hex`: `String` - The hex string to sign.
* **Returns**: `String` - The signed string.

###### `signMessage`

* **Description**: Signs the given message.
* **Parameters**:
  * `message`: `String` - The message to sign.
* **Returns**: `String` - The signed message.

###### `signTypedData`

* **Description**: Signs the given typed data.
* **Parameters**:
  * `typedData`: `String` - The typed data to sign.
* **Returns**: `String` - The signed typed data.

###### `signUserOperation`

* **Description**: Signs the given user operation.
* **Parameters**:
  * `chainId`: `Long` - The chain ID for the user operation. Defaults to the
    chain ID of the client.
  * `userOp`: `UserOperationV07` - The user operation to sign.
* **Returns**: `String` - The signed user operation.

#### Class: `CircleSmartAccount`

* **Description**: Represents a Circle passkey account. A Smart Account
  implemented via a smart contract that adheres to the ERC-4337 interface.
* **Properties**:
  * `client`: `Client` - The blockchain client.
  * `owner`: `Account<SignResult>` - The associated owner account.
  * `entryPoint`: `EntryPoint` - The entry point for the account.
  * `wallet`: Wallet information.
  * `userOperation`: `UserOperationConfiguration?` - Configuration for the User
    Operation.
* **Conforms To**: `SmartAccount`

##### Methods

###### `getAddress`

* **Description**: Retrieves the account address.
* **Returns**: `String` - The account address.

###### `encodeCalls`

* **Description**: Encodes call data arguments.
* **Parameters**:
  * `args`: `[EncodeCallDataArg]` - The call data arguments.
* **Returns**: `String?` - The encoded call data.

###### `getFactoryArgs`

* **Description**: Retrieves factory arguments.
* **Returns**: `(String, String)?` - The factory arguments.
* **Throws**: `BaseError` if there is no initialization code.

###### `getNonce`

* **Description**: Retrieves the account's nonce.
* **Parameters**:
  * `key`: `BigInt?` - Optional key.
* **Returns**: `BigInt` - The nonce value.

###### `getStubSignature`

* **Description**: Retrieves a stub signature for a User Operation.
* **Parameters**:
  * `userOp`: `T` - The User Operation.
* **Returns**: `String` - The stub signature.

###### `sign`

* **Description**: Signs a hex string.
* **Parameters**:
  * `hex`: `String` - The hex string to sign.
* **Returns**: `String` - The signature.
* **Throws**: `BaseError` if signing fails.

###### `signMessage`

* **Description**: Signs a message.
* **Parameters**:
  * `message`: `String` - The message to sign.
* **Returns**: `String` - The signature.
* **Throws**: `BaseError` if signing fails.

###### `signTypedData`

* **Description**: Signs typed data.
* **Parameters**:
  * `jsonData`: `String` - The JSON data to sign.
* **Returns**: `String` - The signature.
* **Throws**: `BaseError` if signing fails.

###### `signUserOperation`

* **Description**: Signs a user operation.
* **Parameters**:
  * `chainId`: `Int` - The chain ID.
  * `userOp`: `UserOperationV07` - The user operation.
* **Returns**: `String` - The signature.
* **Throws**: `BaseError` if signing fails.

###### `getInitCode`

* **Description**: Retrieves the initialization code.
* **Returns**: `String?` - The initialization code.

***

### Utilities

#### Function: `encodeTransfer`

* **Description**: Encodes a transfer function call.
* **Parameters**:
  * `to`: `String` - The recipient address.
  * `token`: `String` - The token contract address or the name of Token enum.
    Supported tokens and their information are listed below.
  * `amount`: `BigInt` - The amount to transfer.
* **Returns**: `EncodeTransferResult` - The encoded transfer ABI and contract
  address.
* Supported Tokens:

##### Mainnet USDC

| Blockchain Network | Enum                | Contract Address                                                                                                                    |
| ------------------ | ------------------- | ----------------------------------------------------------------------------------------------------------------------------------- |
| Arbitrum           | ArbitrumToken.USDC  | [`0xaf88d065e77c8cC2239327C5EDb3A432268e5831`](https://arbiscan.io/token/0xaf88d065e77c8cc2239327c5edb3a432268e5831)                |
| Avalanche          | AvalancheToken.USDC | [`0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E`](https://snowtrace.io/token/0xB97EF9Ef8734C71904D8002F8b6Bc66Dd9c48a6E?chainid=43114) |
| Base               | BaseToken.USDC      | [`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`](https://basescan.org/token/0x833589fcd6edb6e08f4c7c32d4f71b54bda02913)               |
| Monad              | MonadToken.USDC     | [`0x754704Bc059F8C67012fEd69BC8A327a5aafb603`](https://monadvision.com/token/0x754704Bc059F8C67012fEd69BC8A327a5aafb603)            |
| Optimism           | OptimismToken.USDC  | [`0x0b2c639c533813f4aa9d7837caf62653d097ff85`](https://optimistic.etherscan.io/token/0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85)    |
| Polygon            | PolygonToken.USDC   | [`0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359`](https://polygonscan.com/token/0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359)            |
| Unichain           | UnichainToken.USDC  | [`0x078D782b760474a361dDA0AF3839290b0EF57AD6`](https://uniscan.xyz/address/0x078D782b760474a361dDA0AF3839290b0EF57AD6)              |

##### Mainnet Native Tokens

| Blockchain Network | Token Name (Symbol) | Enum              | Contract Address                                                                                                                 |
| ------------------ | ------------------- | ----------------- | -------------------------------------------------------------------------------------------------------------------------------- |
| Arbitrum           | Arbitrum (ARB)      | ArbitrumToken.ARB | [`0x912CE59144191C1204E64559FE8253a0e49E6548`](https://arbiscan.io/token/0x912ce59144191c1204e64559fe8253a0e49e6548)             |
| Optimism           | Optimism (OP)       | OptimismToken.OP  | [`0x4200000000000000000000000000000000000042`](https://optimistic.etherscan.io/token/0x4200000000000000000000000000000000000042) |

##### Testnet USDC

| Blockchain Network | Enum                      | Contract Address                                                                                                                            |
| ------------------ | ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| Arbitrum Sepolia   | ArbitrumSepoliaToken.USDC | [`0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d`](https://sepolia.arbiscan.io/token/0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d)                |
| Arc Testnet        | ArcTestnetToken.USDC      | [`0x3600000000000000000000000000000000000000`](https://testnet.arcscan.app/address/0x3600000000000000000000000000000000000000)              |
| Avalanche Fuji     | AvalancheFujiToken.USDC   | [`0x5425890298aed601595a70AB815c96711a31Bc65`](https://testnet.snowtrace.io/token/0x5425890298aed601595a70AB815c96711a31Bc65?chainid=43113) |
| Base Sepolia       | BaseSepoliaToken.USDC     | [`0x036CbD53842c5426634e7929541eC2318f3dCF7e`](https://base-sepolia.blockscout.com/address/0x036CbD53842c5426634e7929541eC2318f3dCF7e)      |
| Monad Testnet      | MonadTestnetToken.USDC    | [`0x534b2f3A21130d7a60830c2Df862319e593943A3`](https://testnet.monadexplorer.com/token/0x534b2f3A21130d7a60830c2Df862319e593943A3)          |
| Optimism Sepolia   | OptimismSepoliaToken.USDC | [`0x5fd84259d66Cd46123540766Be93DFE6D43130D7`](https://sepolia-optimism.etherscan.io/address/0x5fd84259d66Cd46123540766Be93DFE6D43130D7)    |
| Polygon Amoy       | PolygonAmoyToken.USDC     | [`0x41E94Eb019C0762f9Bfcf9Fb1E58725BfB0e7582`](https://amoy.polygonscan.com/token/0x41E94Eb019C0762f9Bfcf9Fb1E58725BfB0e7582)               |
| Unichain Sepolia   | UnichainSepoliaToken.USDC | [`0x31d0220469e10c4E71834a79b1f276d740d3768F`](https://unichain-sepolia.blockscout.com/address/0x31d0220469e10c4E71834a79b1f276d740d3768F)  |

#### Function: `encodeFunctionData`

* **Description**: Encodes the function name and parameters into an ABI-encoded
  value (4-byte selector and arguments).
* **Parameters**:
  * `functionName`: `String` - The name of the ABI function.
  * `abiJson`: `String` - The ABI JSON.
  * `args`: `[Any]` - The input arguments for the ABI function.
* **Returns**: `String?` - Optional encoded ABI function data.

#### Function: `encodeContractExecution`

* **Description**: Encodes a contract execution into calldata for executing a
  User Operation.
* **Parameters**:
  * `to`: `String` - The target address.
  * `abiSignature`: `String` - The ABI signature of the function.
  * `args`: `[Any]` - The arguments for the function.
  * `value`: `BigInt` - The value to send.
* **Returns**: `String` - The encoded contract execution function data.

#### Function: `parseGweiToWei`

* **Description**: Parses a positive Gwei value to Wei.
* **Parameters**:
  * `value`: `String` - The Gwei value as a string.
* **Returns**: `BigInt` - The Wei value.

#### Function: `parseEtherToWei`

* **Description**: Parses a positive Ether value to Wei.
* **Parameters**:
  * `value`: `String` - The Ether value as a string.
* **Returns**: `BigInt` - The Wei value.

***

### Models

#### Structure: `SignResult`

* **Description**: Represents the result of a signing operation.
* **Properties**:
  * `signature`: `String` - The signature generated by the signing operation.
  * `webAuthn`: `WebAuthnData` - The WebAuthn data associated with the signing
    operation.
  * `raw`: `AuthenticationCredential` - The raw authentication credential used
    in the signing operation.

#### Structure: `WebAuthnData`

* **Description**: Represents WebAuthn data.
* **Properties**:
  * `authenticatorData`: `String` - The authenticator data in hexadecimal
    format.
  * `challengeIndex`: `Int` - The index of the challenge in the client data
    JSON.
  * `clientDataJSON`: `String` - The client data JSON.
  * `typeIndex`: `Int` - The index of the type in the client data JSON.
  * `userVerificationRequired`: `Boolean` - Indicates whether user verification
    is required.

#### Structure: `EncodeCallDataArg`

* **Description**: A struct used to encode call data for smart contracts.
* **Conforms to**: Encodable
* **Properties**:
  * `to`: `String` - The target address for the call (required).
  * `value`: `BigInt?` - The amount of value to send with the call (optional,
    defaults to 0).
  * `data`: `String?` - The call data to be sent (optional, defaults to `"0x"`
    if not provided).
  * `abiJson`: `String?` - The ABI JSON of the smart contract function
    (optional).
  * `args`: `[AnyEncodable]?` - The arguments for the ABI function (optional).
  * `functionName`: `String?` - The name of the function to be called
    (optional).

#### Structure: `EstimateUserOperationGasResult`

* **Description**: Represents the result of estimating gas for a User Operation.
* **Conforms to**: `Codable`
* **Properties**:
  * `preVerificationGas`: `BigInt?` - The gas used for pre-verification.
  * `verificationGasLimit`: `BigInt?` - The gas limit for verification.
  * `callGasLimit`: `BigInt?` - The gas limit for the call.
  * `paymasterVerificationGasLimit`: `BigInt?` - The gas limit for paymaster
    verification.
  * `paymasterPostOpGasLimit`: `BigInt?` - The gas limit for paymaster
    post-operation.

#### Structure: `EstimateFeesPerGasResult`

* **Description**: Represents the result of estimating fees per gas.
* **Properties**:
  * `maxFeePerGas`: `BigInt?` - Maximum fee per gas (EIP-1559).
  * `maxPriorityFeePerGas`: `BigInt?` - Maximum priority fee per gas (EIP-1559).
  * `gasPrice`: `BigInt?` - Legacy gas price.

#### Structure: `GetUserOperationReceiptResult`

* **Description**: Response model for getting a User Operation receipt.
* **Properties**:
  * `userOpHash`: `String?` - The hash of the User Operation.
  * `sender`: `String?` - The sender address.
  * `nonce`: `String?` - The nonce value.
  * `actualGasCost`: `String?` - The actual gas cost in hexadecimal format.
  * `actualGasUsed`: `String?` - The actual gas used in hexadecimal format.
  * `success`: `Boolean?` - Indicates whether the operation was successful.
  * `paymaster`: `String?` - The paymaster address.
  * `logs`: `[Log]?` - The list of logs.
  * `receipt`: `UserOperationReceipt` - The User Operation receipt details.

#### Structure: `GetUserOperationResult`

* **Description**: Represents the result of retrieving a User Operation.
* **Conforms to**: `Codable`
* **Properties**:
  * `blockHash`: `String?` - The hash of the block containing the operation.
  * `blockNumber`: `BigInt?` - The number of the block containing the operation.
  * `transactionHash`: `String?` - The hash of the transaction for the
    operation.
  * `entryPoint`: `String?` - The entry point of the operation.
  * `userOperation`: `UserOperationType?` - The User Operation.

#### Structure: `UserOperationReceipt`

* **Description**: Represents the receipt of a User Operation.
* **Conforms to**: `Codable`
* **Properties**:
  * `transactionHash`: `String?` - The transaction hash.
  * `transactionIndex`: `String?` - The transaction index.
  * `blockHash`: `String?` - The block hash.
  * `blockNumber`: `String?` - The block number.
  * `from`: `String?` - The sender's address.
  * `to`: `String?` - The recipient's address.
  * `cumulativeGasUsed`: `String?` - The cumulative gas used.
  * `gasUsed`: `String?` - The gas used.
  * `logs`: `[Log]?` - The list of logs.
  * `logsBloom`: `String?` - The bloom filter for logs.
  * `status`: `String?` - The status of the operation.
  * `effectiveGasPrice`: `String?` - The effective gas price.

#### Structure: `Log`

* **Description**: Represents a log entry.
* **Conforms to**: `Codable`
* **Properties**:
  * `removed`: `Boolean?` - Indicates whether the log was removed.
  * `logIndex`: `String?` - The index of the log.
  * `transactionIndex`: `String?` - The index of the transaction.
  * `transactionHash`: `String?` - The transaction hash.
  * `blockHash`: `String?` - The block hash.
  * `blockNumber`: `String?` - The block number.
  * `address`: `String?` - The address of the contract generating the log.
  * `data`: `String?` - The log data.
  * `topics`: `[String]?` - The list of topics.

#### Structure: `GetPaymasterDataResult`

* **Description**: Represents the result of retrieving Paymaster data.
* **Conforms to**: `Codable`
* **Properties**:
  * `paymaster`: `String?` - The Paymaster address for entry point version 0.7.
  * `paymasterData`: `String?` - The Paymaster data for entry point version 0.7.
  * `paymasterPostOpGasLimit`: `BigInt?` - The gas limit for the Paymaster
    post-operation for entry point version 0.7.
  * `paymasterVerificationGasLimit`: `BigInt?` - The gas limit for the Paymaster
    verification for entry point version 0.7.
  * `paymasterAndData`: `String?` - The Paymaster and associated data for entry
    point version 0.6.

#### Structure: `GetPaymasterStubDataResult`

* **Description**: Represents the result of retrieving Paymaster stub data.
* **Conforms to**: `Codable`
* **Properties**:
  * `paymaster`: `String?` - The Paymaster address for entry point version 0.7.
  * `paymasterData`: `String?` - The Paymaster data for entry point version 0.7.
  * `paymasterPostOpGasLimit`: `BigInt?` - The gas limit for the Paymaster
    post-operation for entry point version 0.7.
  * `paymasterVerificationGasLimit`: `BigInt?` - The gas limit for the Paymaster
    verification for entry point version 0.7.
  * `paymasterAndData`: `String?` - The Paymaster and associated data for entry
    point version 0.6.
  * `isFinal`: `Boolean?` - Indicates whether the caller does not need to call
    `getPaymasterData`.
  * `sponsor`: `SponsorInfo?` - Sponsor information associated with the
    Paymaster.

#### Structure: `Block`

* **Description**: Represents a block in the Ethereum blockchain.
* **Conforms to**: `Codable`
* **Properties**:
  * `number`: `BigUInt` - The block number.
  * `hash`: `Data` - The block hash.
  * `parentHash`: `Data` - The parent block hash.
  * `nonce`: `Data?` - The block nonce (optional).
  * `sha3Uncles`: `Data` - The SHA3 hash of the uncles.
  * `logsBloom`: `EthereumBloomFilter?` - The bloom filter for the logs
    (optional).
  * `transactionsRoot`: `Data` - The root of the transactions trie.
  * `stateRoot`: `Data` - The root of the state trie.
  * `receiptsRoot`: `Data` - The root of the receipts trie.
  * `miner`: `EthereumAddress?` - The address of the miner.
  * `difficulty`: `BigUInt` - The difficulty of the block.
  * `totalDifficulty`: `BigUInt?` - The total difficulty of the chain up to this
    block.
  * `extraData`: `Data` - Extra data included in the block.
  * `size`: `BigUInt` - The size of the block.
  * `gasLimit`: `BigUInt` - The gas limit of the block.
  * `gasUsed`: `BigUInt` - The gas used in the block.
  * `baseFeePerGas`: `BigUInt?` - The base fee per gas (optional, present in
    EIP-1559 blocks).
  * `timestamp`: `Date` - The timestamp of the block.
  * `transactions`: `[TransactionInBlock]` - The list of transactions in the
    block.
  * `uncles`: `[Data]` - The list of uncle blocks.

#### Structure: `GetUserOperationGasPriceResult`

* **Description**: Represents the result of the `getUserOperationGasPrice`
  method.
* **Conforms to**: `Decodable`
* **Properties**:
  * `low`: `GasPriceOption` - The low-priority gas price option.
  * `medium`: `GasPriceOption` - The medium-priority gas price option.
  * `high`: `GasPriceOption` - The high-priority gas price option.
  * `deployed`: `BigInt?` - The verification gas for a deployed smart account
    (optional).
  * `notDeployed`: `BigInt?` - The verification gas for a non-deployed smart
    account (optional).

#### Structure: `GasPriceOption`

* **Description**: Represents a gas price option.
* **Conforms to**: `Decodable`
* **Properties**:
  * `maxFeePerGas`: `BigInt` - The maximum fee per gas.

#### Structure: `EncodeTransferResult`

* **Description**: The return type for `encodeTransfer`.
* **Properties**:
  * `data`: `String` - The encoded data.
  * `to`: `String` - The token address.

#### Enum: `EntryPoint`

* **Description**: Represents entry points with their respective addresses.
* **Properties**:
  * `address`: `String` - The address of the entry point.
* **Entries**:
  * `v07` - Represents the entry point version 0.7 with its respective address.

#### Class: `Paymaster`

* **Description**: A sealed class for setting User Operation Paymaster
  configuration.
  * If the Paymaster is a `PaymasterClient`, it uses the provided Paymaster
    Client for sponsorship.
  * If the Paymaster is `true`, it assumes that the Bundler Client supports
    Paymaster RPC methods (e.g. `getPaymasterData`) and uses them for
    sponsorship.

##### Subclasses

###### `True`

* **Description**: Represents a Paymaster configuration where the Bundler Client
  supports Paymaster RPC methods.
* **Properties**:
  * `paymasterContext`: `[String: AnyEncodable]?` - Optional context for the
    Paymaster.

###### `Client`

* **Description**: Represents a Paymaster configuration using a provided
  Paymaster Client for sponsorship.
* **Properties**:
  * `client`: `PaymasterClient` - The Paymaster Client used for sponsorship.
  * `paymasterContext`: `[String: AnyEncodable]?` - Optional context for the
    Paymaster.

#### Protocol: `PublicKeyCredential`

* **Description**: Represents a public key credential, with the following
  derived structures:
  * `RegistrationCredential`
  * `AuthenticationCredential`
* **Properties**:
  * `id`: `String` - The unique identifier for the credential.
  * `type`: `String` - The type of the credential.
  * `authenticatorAttachment`: `String` - The attachment type of the
    authenticator.
  * `response`: `AuthenticatorResponse` - The response from the authenticator.
  * `clientExtensionResults`: `AuthenticationExtensionsClientOutputs?` -
    Optional client extension results.

#### Structure: `RegistrationCredential`

* **Description**: Represents a registration credential.
* **Conforms To**: `PublicKeyCredential`
* **Properties**:
  * `rawId`: `String` - The raw identifier for the credential.
  * `authenticatorAttachment`: `String` - The attachment type of the
    authenticator.
  * `type`: `String` - The type of the credential.
  * `id`: `String` - The unique identifier for the credential.
  * `response`: `AuthenticatorAttestationResponse` - The attestation response
    from the authenticator.
  * `clientExtensionResults`: `AuthenticationExtensionsClientOutputs?` -
    Optional client extension results.

#### Structure: `AuthenticationCredential`

* **Description**: Represents an authentication credential.
* **Conforms To**: `PublicKeyCredential`
* **Properties**:
  * `rawId`: `String` - The raw identifier for the credential.
  * `authenticatorAttachment`: `String` - The attachment type of the
    authenticator.
  * `type`: `String` - The type of the credential.
  * `id`: `String` - The unique identifier for the credential.
  * `response`: `AuthenticatorAssertionResponse` - The assertion response from
    the authenticator.
  * `clientExtensionResults`: `AuthenticationExtensionsClientOutputs?` -
    Optional client extension results.

#### Protocol: `UserOperation`

* **Description**: Represents a user operation, with the following derived
  classes:
  * `UserOperationV07`
* **Properties**:
  * `sender`: `String?` - The address of the sender.
  * `nonce`: `BigInt?` - The nonce of the operation.
  * `callData`: `String?` - The data to be sent in the call.
  * `callGasLimit`: `BigInt?` - The gas limit for the call.
  * `verificationGasLimit`: `BigInt?` - The gas limit for verification.
  * `preVerificationGas`: `BigInt?` - The gas used before verification.
  * `maxPriorityFeePerGas`: `BigInt?` - The maximum priority fee per gas.
  * `maxFeePerGas`: `BigInt?` - The maximum fee per gas.
  * `signature`: `String?` - The signature of the operation.

#### Class: `UserOperationV07`

* **Description**: Data class representing a user operation for version 0.7.
* **Conforms To**: `UserOperation`
* **Properties**:
  * `sender`: `String?` - The address of the sender.
  * `nonce`: `BigInt?` - The nonce of the operation.
  * `callData`: `String?` - The data to be sent in the call.
  * `callGasLimit`: `BigInt?` - The gas limit for the call.
  * `verificationGasLimit`: `BigInt?` - The gas limit for verification.
  * `preVerificationGas`: `BigInt?` - The gas used before verification.
  * `maxPriorityFeePerGas`: `BigInt?` - The maximum priority fee per gas.
  * `maxFeePerGas`: `BigInt?` - The maximum fee per gas.
  * `signature`: `String?` - The signature of the operation.
  * `factory`: `String?` - The factory address.
  * `factoryData`: `String?` - The data for the factory.
  * `paymaster`: `String?` - The Paymaster address.
  * `paymasterVerificationGasLimit`: `BigInt?` - The gas limit for Paymaster
    verification.
  * `paymasterPostOpGasLimit`: `BigInt?` - The gas limit for Paymaster
    post-operation.
  * `paymasterData`: `String?` - The data for the Paymaster.

#### Enum: `WebAuthnMode`

* **Description**: Represents the WebAuthn modes.
* **Entries**:
  * `Register` - Mode for registering a new credential.
  * `Login` - Mode for logging in with an existing credential.

#### Enum: `ArbitrumToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`
  * `ARB`

#### Enum: `ArbitrumSepoliaToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `ArcToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `ArcTestnetToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `AvalancheToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `AvalancheFujiToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `BaseToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `BaseSepoliaToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `OptimismToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`
  * `OP`

#### Enum: `OptimismSepoliaToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `PolygonToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `PolygonAmoyToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `UnichainToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Enum: `UnichainSepoliaToken`

* **Description**: Enum representing various tokens supported by
  `encodeTransfer`. The format is `{chain}_{symbol}`.
* **Entries**:
  * `USDC`

#### Structure: `ModularWallet`

* **Description**: Represents a wallet entity within the system.
* **Conforms To**: `Codable`
* **Properties**:
  * `id`: `String?` - The unique identifier of the wallet.
  * `address`: `String?` - The blockchain address of the wallet.
  * `blockchain`: `String?` - The blockchain network the wallet is associated
    with.
  * `state`: `String?` - The current state of the wallet.
  * `name`: `String?` - The name of the wallet.
  * `scaCore`: `String?` - The SCA (Strong Customer Authentication) core
    identifier.
  * `scaConfiguration`: `ScaConfiguration?` - The SCA configuration associated
    with the wallet.
  * `createDate`: `String?` - The creation date of the wallet.
  * `updateDate`: `String?` - The last update date of the wallet.

##### Methods

###### `getInitCode`

* **Description**: Retrieves the initialization code for the wallet.
* **Returns**: `String?` - The initialization code from the SCA configuration,
  if available.

***

### Chains

#### Protocol: `Chain`

* **Description**: Abstract class representing the necessary definitions of a
  blockchain for the SDK.
* **Predefined Chains**:
  * `Arbitrum`
  * `ArbitrumSepolia`
  * `Arc`
  * `ArcTestnet`
  * `Avalanche`
  * `AvalancheFuji`
  * `Base`
  * `BaseSepolia`
  * `Monad`
  * `MonadTestnet`
  * `Optimism`
  * `OptimismSepolia`
  * `Polygon`
  * `PolygonAmoy`
  * `Unichain`
  * `UnichainSepolia`
* **Properties**:
  * `chainId`: `Int` - The unique identifier for the blockchain.