title: "Text-to-speech"

---

OpenClaw can convert outbound replies into audio using ElevenLabs, Google Gemini, Gradium, Microsoft, MiniMax, OpenAI, Vydra, or xAI.

OpenClaw can convert outbound replies into audio using ElevenLabs, Google Gemini, Gradium, Microsoft, MiniMax, OpenAI, Vydra, xAI, or Xiaomi MiMo.

It works anywhere OpenClaw can send audio.

## Supported services

- **OpenAI** (primary or fallback provider; also used for summaries)

- **Vydra** (primary or fallback provider; shared image, video, and speech provider)

- **xAI** (primary or fallback provider; uses the xAI TTS API)

- **Xiaomi MiMo** (primary or fallback provider; uses MiMo TTS through Xiaomi chat completions)

### Microsoft speech notes

## Optional keys

If you want OpenAI, ElevenLabs, Google Gemini, Gradium, MiniMax, Vydra, or xAI:

If you want OpenAI, ElevenLabs, Google Gemini, Gradium, MiniMax, Vydra, xAI, or Xiaomi MiMo:

- `ELEVENLABS_API_KEY` (or `XI_API_KEY`)

- `GEMINI_API_KEY` (or `GOOGLE_API_KEY`)

- `OPENAI_API_KEY`

- `VYDRA_API_KEY`

- `XAI_API_KEY`

- `XIAOMI_API_KEY`

Microsoft speech does **not** require an API key.

- [ElevenLabs Authentication](https://elevenlabs.io/docs/api-reference/authentication)

- [Gradium](/providers/gradium)

- [MiniMax T2A v2 API](https://platform.minimaxi.com/document/T2A%20V2)

- [Xiaomi MiMo speech synthesis](/providers/xiaomi#text-to-speech)

- [node-edge-tts](https://github.com/SchneeHertz/node-edge-tts)

- [Microsoft Speech output formats](https://learn.microsoft.com/azure/ai-services/speech-service/rest-text-to-speech#audio-outputs)

- [xAI Text to Speech](https://docs.x.ai/developers/rest-api-reference/inference/voice#text-to-speech-rest)

Current live voices are `ara`, `eve`, `leo`, `rex`, `sal`, and `una`; `eve` is

the default. `language` accepts a BCP-47 tag or `auto`.

### Xiaomi MiMo primary

```json5

{

messages: {

tts: {

auto: "always",

provider: "xiaomi",

providers: {

xiaomi: {

apiKey: "xiaomi_api_key",

baseUrl: "https://api.xiaomimimo.com/v1",

model: "mimo-v2.5-tts",

voice: "mimo_default",

format: "mp3",

style: "Bright, natural, conversational tone.",

},

},

},

},

}

```

Xiaomi MiMo TTS uses the same `XIAOMI_API_KEY` path as the bundled Xiaomi model

provider. The speech provider id is `xiaomi`; `mimo` is accepted as an alias.

The target text is sent as the assistant message, matching Xiaomi's TTS

contract. Optional `style` is sent as a user instruction and is not spoken.

### OpenRouter primary

```json5

- `tagged` only sends audio when the reply includes `[[tts:key=value]]` directives or a `[[tts:text]]...[[/tts:text]]` block.

- `enabled`: legacy toggle (doctor migrates this to `auto`).

- `mode`: `"final"` (default) or `"all"` (includes tool/block replies).

- `provider`: speech provider id such as `"elevenlabs"`, `"google"`, `"gradium"`, `"microsoft"`, `"minimax"`, `"openai"`, `"vydra"`, or `"xai"` (fallback is automatic).

- `provider`: speech provider id such as `"elevenlabs"`, `"google"`, `"gradium"`, `"microsoft"`, `"minimax"`, `"openai"`, `"vydra"`, `"xai"`, or `"xiaomi"` (fallback is automatic).

- If `provider` is **unset**, OpenClaw uses the first configured speech provider in registry auto-select order.

- Legacy `provider: "edge"` config is repaired by `openclaw doctor --fix` and

rewritten to `provider: "microsoft"`.

- `maxTextLength`: hard cap for TTS input (chars). `/tts audio` fails if exceeded.

- `timeoutMs`: request timeout (ms).

- `prefsPath`: override the local prefs JSON path (provider/limit/summary).

- `apiKey` values fall back to env vars (`ELEVENLABS_API_KEY`/`XI_API_KEY`, `GEMINI_API_KEY`/`GOOGLE_API_KEY`, `GRADIUM_API_KEY`, `MINIMAX_API_KEY`, `OPENAI_API_KEY`, `VYDRA_API_KEY`, `XAI_API_KEY`).

- `apiKey` values fall back to env vars (`ELEVENLABS_API_KEY`/`XI_API_KEY`, `GEMINI_API_KEY`/`GOOGLE_API_KEY`, `GRADIUM_API_KEY`, `MINIMAX_API_KEY`, `OPENAI_API_KEY`, `VYDRA_API_KEY`, `XAI_API_KEY`, `XIAOMI_API_KEY`).

- `providers.elevenlabs.baseUrl`: override ElevenLabs API base URL.

- `providers.openai.baseUrl`: override the OpenAI TTS endpoint.

- Resolution order: `messages.tts.providers.openai.baseUrl` -> `OPENAI_TTS_BASE_URL` -> `https://api.openai.com/v1`

- `providers.xai.language`: BCP-47 language code or `auto` (default `en`).

- `providers.xai.responseFormat`: `mp3`, `wav`, `pcm`, `mulaw`, or `alaw` (default `mp3`).

- `providers.xai.speed`: provider-native speed override.

- `providers.xiaomi.apiKey`: Xiaomi MiMo API key (env: `XIAOMI_API_KEY`).

- `providers.xiaomi.baseUrl`: override the Xiaomi MiMo API base URL (default `https://api.xiaomimimo.com/v1`, env: `XIAOMI_BASE_URL`).

- `providers.xiaomi.model`: TTS model (default `mimo-v2.5-tts`, env: `XIAOMI_TTS_MODEL`; `mimo-v2-tts` is also supported).

- `providers.xiaomi.voice`: MiMo voice id (default `mimo_default`, env: `XIAOMI_TTS_VOICE`).

- `providers.xiaomi.format`: `mp3` or `wav` (default `mp3`, env: `XIAOMI_TTS_FORMAT`).

- `providers.xiaomi.style`: optional natural-language style instruction sent as the user message; it is not spoken.

- `providers.openrouter.apiKey`: OpenRouter API key (env: `OPENROUTER_API_KEY`; can reuse `models.providers.openrouter.apiKey`).

- `providers.openrouter.baseUrl`: override the OpenRouter TTS base URL (default `https://openrouter.ai/api/v1`; legacy `https://openrouter.ai/v1` is normalized).

- `providers.openrouter.model`: OpenRouter TTS model id (default `hexgrad/kokoro-82m`; `modelId` is also accepted).

Available directive keys (when enabled):

- `provider` (registered speech provider id, for example `openai`, `elevenlabs`, `google`, `gradium`, `minimax`, `microsoft`, `vydra`, or `xai`; requires `allowProvider: true`)

- `voice` (OpenAI or Gradium voice), `voiceName` / `voice_name` / `google_voice` (Google voice), or `voiceId` (ElevenLabs / Gradium / MiniMax / xAI)

- `model` (OpenAI TTS model, ElevenLabs model id, or MiniMax model) or `google_model` (Google TTS model)

- `provider` (registered speech provider id, for example `openai`, `elevenlabs`, `google`, `gradium`, `minimax`, `microsoft`, `vydra`, `xai`, or `xiaomi`; requires `allowProvider: true`)

- `voice` (OpenAI, Gradium, or Xiaomi voice), `voiceName` / `voice_name` / `google_voice` (Google voice), or `voiceId` (ElevenLabs / Gradium / MiniMax / xAI)

- `model` (OpenAI TTS model, ElevenLabs model id, MiniMax model, or Xiaomi MiMo TTS model) or `google_model` (Google TTS model)

- `stability`, `similarityBoost`, `style`, `speed`, `useSpeakerBoost`

- `vol` / `volume` (MiniMax volume, 0-10)

- `pitch` (MiniMax integer pitch, -12 to 12; fractional values are truncated before the MiniMax request)

- **Other channels**: MP3 (`mp3_44100_128` from ElevenLabs, `mp3` from OpenAI).

- 44.1kHz / 128kbps is the default balance for speech clarity.

- **MiniMax**: MP3 (`speech-2.8-hd` model, 32kHz sample rate) for normal audio attachments. For voice-note targets such as Feishu and Telegram, OpenClaw transcodes the MiniMax MP3 to 48kHz Opus with `ffmpeg` before delivery.

- **Xiaomi MiMo**: MP3 by default, or WAV when configured. For voice-note targets such as Feishu and Telegram, OpenClaw transcodes Xiaomi output to 48kHz Opus with `ffmpeg` before delivery.

- **Google Gemini**: Gemini API TTS returns raw 24kHz PCM. OpenClaw wraps it as WAV for audio attachments and returns PCM directly for Talk/telephony. Native Opus voice-note format is not supported by this path.

- **Gradium**: WAV for audio attachments, Opus for voice-note targets, and `ulaw_8000` at 8 kHz for telephony.

- **xAI**: MP3 by default; `responseFormat` may be `mp3`, `wav`, `pcm`, `mulaw`, or `alaw`. OpenClaw uses xAI's batch REST TTS endpoint and returns a complete audio attachment; xAI's streaming TTS WebSocket is not used by this provider path. Native Opus voice-note format is not supported by this path.