## Documentation Index

Fetch the complete documentation index at: [/llms.txt](https://docs.relay.link/llms.txt)

Use this file to discover all available pages before exploring further.

The `fastFill` action allows you to accelerate the filling of a cross-chain request on the destination chain. This is useful when you want to speed up the completion of a bridge or swap operation.[Learn more about the Fast Fill API](https://docs.relay.link/references/api/fast-fill)

## Parameters

| Property | Description | Required |
| --- | --- | --- |
| **requestId** | The unique identifier of the request to fast fill | ✅ |
| **solverInputCurrencyAmount** | The amount of input currency the solver should use for filling. This is useful if you know the finalized input amount which can help to minimize slippage. If not specified, uses the quoted amount. | ❌ |

## Example

```
import { getClient } from "@relayprotocol/relay-sdk";

const requestId = "0x..."; // The request ID from a previous quote/execute

const result = await getClient().actions.fastFill({
  requestId,
});
```

## Example with Solver Input Amount

```
import { getClient } from "@relayprotocol/relay-sdk";

const requestId = "0x..."; // The request ID from a previous quote/execute

const result = await getClient().actions.fastFill({
  requestId,
  solverInputCurrencyAmount: "1000000000000000000", // 1 token in wei
});
```