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

# useSendToolListChanged

> Notify the host that the app's tool list changed.

<Badge color="yellow">sunpeak API</Badge>

## Overview

Returns a function to notify the host that the app's available tools have changed. Call this after registering, removing, enabling, or disabling tools via [`useRegisterTool`](/app-framework/hooks/use-register-tool).

## Import

```tsx theme={null}
import { useSendToolListChanged } from 'sunpeak';
```

## Signature

```tsx theme={null}
function useSendToolListChanged(): () => Promise<void>
```

## Returns

<ResponseField name="sendToolListChanged" type="() => Promise<void>">
  Function that sends a `tools/list_changed` notification to the host.
</ResponseField>

## Usage

```tsx theme={null}
import { useRegisterTool, useSendToolListChanged } from 'sunpeak';

function DynamicTools() {
  const registerTool = useRegisterTool();
  const sendToolListChanged = useSendToolListChanged();

  const addTool = () => {
    registerTool("ping", { description: "Ping" }, () => ({
      content: [{ type: "text", text: "pong" }],
    }));
    sendToolListChanged();
  };

  return <button onClick={addTool}>Add Tool</button>;
}
```