> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mobula.io/llms.txt
> Use this file to discover all available pages before exploring further.

# FrontRunLabelData

> Payload for an EventLabel with label=FrontRun. Identifies the leg (front-run or back-run) and reports the swap's token amounts as drained-amount magnitudes.

### TypeScript shape

```ts theme={null}
interface FrontRunLabelData {
  index: number | null;
  token0DrainedAmount: string;
  token1DrainedAmount: string;
}
```

<ResponseField name="__typename" type="String!">Always `"FrontRunLabelData"`.</ResponseField>
<ResponseField name="index" type="Int">Leg index. `0` = front-run (buy leg, token0 entered the pool). `1` = back-run (sell leg). Derived from the sign of the swap's `raw_amount0`.</ResponseField>
<ResponseField name="token0DrainedAmount" type="String!">Unsigned magnitude of the swap's token0 movement. Sign stripped at the API edge.</ResponseField>
<ResponseField name="token1DrainedAmount" type="String!">Unsigned magnitude of the swap's token1 movement.</ResponseField>