# FOCIL with geth

## Engine APIs

## Constants

| Name | Value |
| - | - |
| `MaxBytesPerInclusionList` | `uint64(8192) = 2**13` |

## Structures

### InclusionListV1

This structure contains a list of transactions. The fields are encoded as follows:
- `transactions`: `Array of DATA` - Array of transaction objects, each object is a byte list (`DATA`) representing `TransactionType || TransactionPayload` or `LegacyTransaction` as defined in [EIP-2718](https://eips.ethereum.org/EIPS/eip-2718)

### UpdateInclusionListResponse

This structure contains an identifier of the payload build process that is requested to update with the given inclusion list.
- `payloadId`: `DATA`, 8 Bytes - Identifier of the payload build process

## Methods

### engine_newPayloadV5

The request of this method is updated with [`ExecutionPayloadV3`](https://github.com/ethereum/execution-apis/blob/main/src/engine/cancun.md#executionpayloadv3).

#### Request

* method: `engine_newPayloadV5`
* params:
1. `executionPayload`: [`ExecutionPayloadV3`](https://github.com/ethereum/execution-apis/blob/main/src/engine/cancun.md#executionpayloadv3).
2. `expectedBlobVersionedHashes`: `Array of DATA`, 32 Bytes - Array of expected blob versioned hashes to validate.
3. `parentBeaconBlockRoot`: `DATA`, 32 Bytes - Root of the parent beacon block.
4. `inclusionList`: [`InclusionListV1`](#InclusionListV1).

#### Response

Refer to the response for [`engine_newPayloadV4`](https://github.com/ethereum/execution-apis/blob/main/src/engine/prague.md#engine_newpayloadv4).

#### Specification

This method follows the same specification as [`engine_newPayloadV4`](https://github.com/ethereum/execution-apis/blob/main/src/engine/prague.md#engine_newpayloadv4) with the following changes:

1. Client software **MUST** return `{status: INVALID_INCLUSION_LIST, latestValidHash: null, validationError: null}` if there are any transactions of `inclusionList` that are not part of the `executionPayload`, even if they can be appended at the end of the `executionPayload`.

### engine_getInclusionListV1

#### Request

* method: `engine_getInclusionListV1`
* params:
1. `parentHash`: `DATA`, 32 Bytes - parent hash which returned inclusion list should be built upon.
* timeout: 1s

#### Response

* result: [`InclusionListV1`](#InclusionListV1).
* error: code and message set in case an exception happens while getting the inclusion list.

#### Specification

1. Client software **MUST** provide a list of transactions for the inclusion list based on local view of the mempool and according to the config specifications.

### engine_updatePayloadWithInclusionListV1

#### Request

* method: `engine_updatePayloadWithInclusionListV1`
* params:
1. `payloadId`: `DATA`, 8 Bytes - Identifier of the payload build process.
2. `inclusionList`: [`InclusionListV1`](#InclusionListV1).
* timeout: 1s

#### Response

* result: [`UpdateInclusionListResponse`](#UpdateInclusionListResponse).
* error: code and message set in case an exception happens while getting the inclusion list.

#### Specification

1. Given the `payloadId` client software **MUST** update payload build process building with `inclusionList`. The transactions must be part of the execution payload unless it fails to be included at the end of it.