Who pays for gas

Every transaction from a Startale smart account is an ERC-4337 UserOperation. The gas for that operation is paid either by a paymaster that co-signs it, or by the smart account itself out of its own ETH balance. Which of the two applies is decided by one thing: where your application runs.

​

The two contexts

​

Mini Apps are sponsored by the Startale App

Transactions that originate from a Mini App running inside the Startale App are sponsored by Startale. Gas is invisible to your code and to the user, and there is nothing to configure. Do not set paymasterOptions in a Mini App; the host uses its own paymaster and ignores yours. Sponsorship carries two limits:

• Ethereum Mainnet is capped per user. Mini Apps run on Soneium only unless enabled for another chain. For a Mini App enabled for Ethereum Mainnet, the first three Ethereum Mainnet transactions per user are sponsored, counted per user across the Startale App. After that the user pays from their smart account’s ETH balance. Soneium transactions are not capped.
• Sponsorship is an operated service, not a guarantee. Startale can withdraw sponsorship for a specific app, for example when its transactions generate abnormal gas cost. If that happens the user pays, and your flows should surface the resulting failure rather than retrying silently.

See Gas in a Mini App for the Mini App call sites.

​

Standalone applications supply their own paymaster

When your application uses @startale/app-sdk from your own origin, Startale does not sponsor its gas. You choose between two outcomes:

1. You pay. Configure a paymaster through paymasterOptions. The Startale App forwards paymaster requests to the service you name and your paymaster settles the gas.
2. The user pays. Configure nothing. The UserOperation is still built and submitted, and gas comes out of the user’s smart account ETH balance.

There is no third option in which Startale absorbs the cost. Both outcomes are supported, and choosing the second is a legitimate decision for internal tooling or for applications whose users already hold ETH. It is not a legitimate default for a consumer flow, because a user with an empty smart account simply cannot transact. Gas in a standalone application covers both paths in code.

​

Where Startale’s responsibility ends

For a standalone application, the Startale App accepts a paymaster URL from your application and forwards ERC-7677 paymaster requests to it. That forwarding is the extent of the platform’s involvement. Everything about the paymaster itself is operated by you. Your paymaster URL travels in your application’s client code, so treat it as public from the first day. A paymaster that accepts any request from any caller will be drained by someone other than your users. Secure your paymaster is not optional reading.

​

Which paymaster services work

Any service that implements ERC-7677 works. The integration is provider-neutral: the App SDK attaches your paymaster URL to the request as a paymasterService capability, and the Startale App forwards pm_getPaymasterStubData and pm_getPaymasterData to it, whoever operates it. Common choices are a hosted gas manager from an infrastructure provider, or a service you run yourself when you need sponsorship rules a hosted product cannot express.

​

Pick your path