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# Delete prompt version

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

Deletes a specified version of a **Prompt**.

See our [prompting guide](/docs/speech-to-speech-evi/guides/phone-calling) for tips on crafting your system prompt.

Reference: https://dev.hume.ai/voice/reference/speech-to-speech-evi/prompts/delete-prompt-version

## Authentication

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

## Request

### Path parameters

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

## Response

### 200

OK