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

> ## Agent Instructions
> Public hosts only: console https://omnimux.ai/dashboard · API https://api.omnimux.ai · docs https://docs.omnimux.ai.
> Gateway auth is Authorization: Bearer sk-… on https://api.omnimux.ai/v1 (OpenAI-compatible Chat Completions and related paths).
> Discover pages from /llms.txt; full site dump /llms-full.txt; product skill /skill.md; docs search MCP /mcp. Prefer .md page URLs for Markdown.
> Default docs locale is en; zh mirrors the same relative paths. Do not invent model ids not present on live pricing or the complete API pages.

# GPT-4o mini TTS

> GPT-4o mini TTS · model `gpt-4o-mini-tts`

* Call `POST /v1/audio/speech` with `model` `gpt-4o-mini-tts`
* Body requires `model`, `input`, and `voice`
* Returns binary audio stream (`audio/mpeg` by default)

## Identity

| Field  | Value             |
| ------ | ----------------- |
| Series | Audio series      |
| Brand  | GPT Audio         |
| model  | `gpt-4o-mini-tts` |

## Endpoint

| Method | Path               |
| ------ | ------------------ |
| `POST` | `/v1/audio/speech` |

Base URL: `https://api.omnimux.ai`

## Authorizations

| Name            | In     | Type   | Required | Description               |
| --------------- | ------ | ------ | -------- | ------------------------- |
| `Authorization` | header | string | yes      | `Bearer sk-...` (API key) |

## Body

| Field             | Type   | Required | Description                                                              |
| ----------------- | ------ | -------- | ------------------------------------------------------------------------ |
| `model`           | string | yes      | Must be `gpt-4o-mini-tts`                                                |
| `input`           | string | yes      | Text to synthesize (up to 4096 characters)                               |
| `voice`           | string | yes      | Voice persona (e.g. `alloy`, `echo`, `fable`, `onyx`, `nova`, `shimmer`) |
| `response_format` | string | no       | `mp3` (default), `opus`, `aac`, `flac`, `wav`, `pcm`                     |
| `speed`           | number | no       | Speaking speed multiplier (`0.25` to `4.0`, default `1.0`)               |

## Response

### 200

Returns binary audio data with `Content-Type: audio/mpeg`.

Errors: see right-rail examples.

<Panel>
  <RequestExample>
    ```bash curl --request POST \ theme={null}
      --url https://api.omnimux.ai/v1/audio/speech \
      --header 'Authorization: Bearer <token>' \
      --header 'Content-Type: application/json' \
      --data '{
      "model": "gpt-4o-mini-tts",
      "input": "Hello! Welcome to OmniMux text-to-speech API.",
      "voice": "alloy"
    }' \
      --output speech.mp3
    ```
  </RequestExample>

  <ResponseExample>
    ```json 400 theme={null}
    { "error": { "message": "Invalid request", "type": "invalid_request_error", "code": "bad_request" } }
    ```

    ```json 401 theme={null}
    { "error": { "message": "Invalid token", "type": "authentication_error", "code": "unauthorized" } }
    ```

    ```json 402 theme={null}
    {
      "error": {
        "message": "Insufficient quota. Please top up your account.",
        "type": "insufficient_quota",
        "code": "insufficient_quota"
      }
    }
    ```

    ```json 429 theme={null}
    { "error": { "message": "Rate limit exceeded", "type": "rate_limit_error", "code": "rate_limit_exceeded" } }
    ```

    ```json 500 theme={null}
    { "error": { "message": "Internal server error", "type": "server_error", "code": "internal_error" } }
    ```
  </ResponseExample>
</Panel>