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# Delete tool version

DELETE https://api.hume.ai/v0/evi/tools/{id}/version/{version}

Deletes a specified version 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/delete-tool-version

## 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.
- `version` (integer, required) — Version number for a Tool. Tools, Configs, Custom Voices, and Prompts are versioned. This versioning system supports iterative development, allowing you to progressively refine tools and revert to previous versions if needed. Version numbers are integer values representing different iterations of the Tool. Each update to the Tool increments its version number.

## Response

### 200

OK