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# Update tool name

PATCH https://api.hume.ai/v0/evi/tools/{id}
Content-Type: application/json

Updates the name of a **Tool**.

Refer to our [tool use](/docs/speech-to-speech-evi/features/tool-use#function-calling) guide for comprehensive instructions on defining and integrating tools into EVI.

Reference: https://dev.hume.ai/voice/reference/speech-to-speech-evi/tools/update-tool-name

## Authentication

- `X-Hume-Api-Key` header (required) — API Key authentication via header

## Request

### Path parameters

- `id` (string, required) — Identifier for a Tool. Formatted as a UUID.

### Body (application/json)

This endpoint expects a posted_user_defined_tool_name.

- `name` (string, required) — Name of the built-in tool to use. Hume supports the following built-in tools: - **web_search:** enables EVI to search the web for up-to-date information when applicable. - **hang_up:** closes the WebSocket connection when appropriate (e.g., after detecting a farewell in the conversation). For more information, see our guide on [using built-in tools](/docs/speech-to-speech-evi/features/tool-use#using-built-in-tools).

## Response

### 200

Success

## Examples

**Request**

```json
{
  "name": "get_current_temperature"
}
```