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# Interface: HookEventPayload<Event>

> Generated from the public TypeScript API.

A hook invocation with session/tool identity, cancellation signal and event-specific data.

## Type Parameters

### Event

`Event` *extends* [`HookEventName`](../type-aliases/HookEventName) = [`HookEventName`](../type-aliases/HookEventName)

## Properties

### data

```ts theme={null}
data: HookData<Event>;
```

***

### event

```ts theme={null}
event: Event;
```

***

### rootSessionId?

```ts theme={null}
optional rootSessionId?: string;
```

***

### sessionId

```ts theme={null}
sessionId: string;
```

***

### signal

```ts theme={null}
signal: AbortSignal;
```

***

### toolCallId?

```ts theme={null}
optional toolCallId?: string;
```


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