Low-Level InfraBundler

Bundler API Endpoints

The Bundler API Endpoints allow you to interact with the lowest level of the account abstraction stack.

What is the Bundler API?

The Bundler APIs are a collection of ERC-4337 compliant JSON-RPC endpoints which makes it possible for users to work with user operations. Below are the Bundler API endpoints available and the corresponding docs for each of them.

MethodDescription
eth_sendUserOperationSubmits a user operation to a Bundler. If the request is successful, the endpoint will return a user operation hash that the caller can use to look up the status of the user operation. If it fails, or another error occurs, an error code and description will be returned.
eth_estimateUserOperationGasEstimates the gas values for a user operation. It returns the [preVerificationGas], [verificationGasLimit], and [callGasLimit] values associated with the provided user operation.
eth_getUserOperationByHashReturns a user operation based on the given user operation hash. It returns the user operation along with extra information including what block/transaction it was included in. If the operation has not yet been included, it will return [null].
eth_getUserOperationReceiptReturns a user operation receipt ( metadata associated with the given user operation ) based on the given user operation hash. It returns [null] if the user operation has not yet been included.
rundler_maxPriorityFeePerGasReturns a fee per gas that is an estimate of how much users should set as a priority fee in UOs for Rundler endpoints.
eth_supportedEntryPointsReturns a list of Entrypoint contract addresses supported by the bundler endpoints.