EIP-7702 developer guide

EIP-7702 lets an existing EOA delegate execution to a smart contract while keeping the same address. Combined with the Startale Smart Account, that means you can take any EOA and start sending UserOperations from it without migrating funds, rotating keys, or asking the user to remember a new address.

Source: StartaleGroup/scs-aa-sdk.

What EIP-7702 does, in one diagram

The address is unchanged. What changes is the code at that address: a 23-byte delegation indicator (0xef0100 || implementation) that tells the EVM to execute the implementation’s code whenever the address is called. To revert, the user signs a new authorization that points at the zero address.

Why use it

Benefit	Detail
No address change	Funds, allowances, and onchain history follow the user.
No deploy step	Authorization is included in a transaction; the EVM applies the delegation at execution time.
All AA features unlocked	Sponsored gas, ERC-20 gas, sessions, recovery, and batched calls become available on an EOA.
Reversible	Authorization for `0x0` clears the delegation.

Prerequisites

A signer for the EOA you want to upgrade (private key, wallet client, EIP-1193 provider, or ethers wallet).
The Startale account implementationAddress (see Contracts and audits).
The bundler and paymaster URLs from the SCS Portal.

npm install @startale-scs/aa-sdk viem

Path A: automatic authorization (recommended)

When you pass eip7702Account to toStartaleSmartAccount, the SDK signs the authorization for you on the next UserOperation. This is the cleanest integration: the user signs once, the delegation is applied as part of the same UserOp, and you keep using the same StartaleAccountClient afterwards.

import { http, createPublicClient } from "viem"
import { privateKeyToAccount } from "viem/accounts"
import { soneiumMinato } from "viem/chains"
import {
  createSCSPaymasterClient,
  createSmartAccountClient,
  toStartaleSmartAccount,
} from "@startale-scs/aa-sdk"

const signer = privateKeyToAccount(process.env.OWNER_PRIVATE_KEY as `0x${string}`)
const eoaAddress = signer.address

const publicClient = createPublicClient({ chain: soneiumMinato, transport: http() })

const paymasterClient = createSCSPaymasterClient({
  transport: http(process.env.PAYMASTER_URL!),
})

const smartAccountClient = createSmartAccountClient({
  account: await toStartaleSmartAccount({
    signer,
    chain: soneiumMinato,
    transport: http(),
    accountAddress: eoaAddress,
    eip7702Account: signer,
  }),
  transport: http(process.env.BUNDLER_URL!),
  client: publicClient,
  paymaster: paymasterClient,
  paymasterContext: {
    paymasterId: process.env.PAYMASTER_ID!,
  },
})

Symbol	Source	Role
`privateKeyToAccount`	`viem/accounts`	Builds a viem `LocalAccount` for the EOA.
`accountAddress`	`toStartaleSmartAccount` parameter	Pins the smart account to the EOA’s address instead of deriving a new counterfactual one.
`eip7702Account`	`toStartaleSmartAccount` parameter	When set, the SDK uses this signer to sign the EIP-7702 authorization on the next UserOp.
`paymasterContext.paymasterId`	request flag	Optional. Sponsoring the upgrade UserOp removes the need for the EOA to hold ETH.

Path B: manual authorization

If you need to inspect or persist the authorization yourself (for example, to store it server-side), sign it explicitly with a viem WalletClient and pass the result as eip7702Auth.

import { createWalletClient, http } from "viem"
import { soneiumMinato } from "viem/chains"
import { toStartaleSmartAccount } from "@startale-scs/aa-sdk"

const walletClient = createWalletClient({
  account: signer,
  chain: soneiumMinato,
  transport: http(),
})

const authorization = await walletClient.signAuthorization({
  contractAddress: process.env.STARTALE_ACCOUNT_IMPLEMENTATION_ADDRESS as `0x${string}`,
})

const account = await toStartaleSmartAccount({
  signer,
  chain: soneiumMinato,
  transport: http(),
  accountAddress: signer.address,
  eip7702Auth: authorization,
})

Symbol	Source	Role
`walletClient.signAuthorization`	`viem`	Returns a `SignAuthorizationReturnType` over `{ chainId, address, nonce, ... }`.
`eip7702Auth`	`toStartaleSmartAccount` parameter	A pre-signed authorization to attach to the next UserOp.

Use Path B when you want to:

Prepare authorizations server-side and ship them to the client.
Sign once with a hardware-backed wallet and reuse the result.
Inspect the structure of the authorization before submitting it.

Send a UserOperation

After either path, the client behaves like any other Startale account client:

const hash = await smartAccountClient.sendUserOperation({
  calls: [{ to: target, data: callData, value: 0n }],
})
const receipt = await smartAccountClient.waitForUserOperationReceipt({ hash })

The first UserOp also lands the EIP-7702 delegation; subsequent ones simply use it.

Inspect and revert

The smart account exposes EIP-7702 helpers directly:

const isDelegated = await smartAccountClient.account.isDelegated()

if (isDelegated) {
  const tx = await smartAccountClient.account.unDelegate()
  await publicClient.waitForTransactionReceipt({ hash: tx })
}

Method	Source	Role
`account.isDelegated()`	`@startale-scs/aa-sdk`	Reads the EOA’s code and checks for the `0xef0100` prefix.
`account.unDelegate()`	`@startale-scs/aa-sdk`	Submits an authorization for the zero address, clearing the delegation.

Caveats

Some external wallets restrict EIP-7702 delegation to their own implementation contracts. If your users sign through a wallet that enforces this, you cannot delegate them to the Startale implementation; use a viem LocalAccount or a Privy/Dynamic embedded wallet instead.

The authorization is chain-specific unless you set chainId = 0. Use a fresh authorization per chain in normal flows.
Delegating bumps the EOA’s nonce, just like any other transaction.
Reverting (unDelegate) also bumps the nonce.

Next steps

Smart account setup

Wire the EIP-7702 client into a React provider.

Smart sessions

Issue session keys for the upgraded EOA.

Contracts and audits

Look up the implementation address per network.

Overview

Getting started

Tutorials

Auth providers

Advanced

EIP-7702

Resources

FAQ

What EIP-7702 does, in one diagram

Why use it

Prerequisites

Path A: automatic authorization (recommended)

Path B: manual authorization

Send a UserOperation

Inspect and revert

Caveats

Next steps

Smart account setup

Sponsored paymaster

Smart sessions

Contracts and audits

​What EIP-7702 does, in one diagram

​Why use it

​Prerequisites

​Path A: automatic authorization (recommended)

​Path B: manual authorization

​Send a UserOperation

​Inspect and revert

​Caveats

​Next steps

Smart account setup

Sponsored paymaster

Smart sessions

Contracts and audits

What EIP-7702 does, in one diagram

Why use it

Prerequisites

Path A: automatic authorization (recommended)

Path B: manual authorization

Send a UserOperation

Inspect and revert

Caveats

Next steps