Inworld

Inworld is a streaming text-to-speech (TTS) provider. In OpenClaw it synthesizes outbound reply audio (MP3 by default, OGG_OPUS for voice notes) and PCM audio for telephony channels such as Voice Call.

OpenClaw posts to Inworld's streaming TTS endpoint, concatenates the returned base64 audio chunks into a single buffer, and hands the result to the standard reply-audio pipeline.

Detail	Value
Website	inworld.ai
Docs	docs.inworld.ai/tts/tts
Auth	INWORLD_API_KEY (HTTP Basic, Base64 dashboard credential)
Default voice	Sarah
Default model	inworld-tts-1.5-max

Getting started

<Steps> <Step title="Set your API key"> Copy the credential from your Inworld dashboard (Workspace > API Keys) and set it as an env var. The value is sent verbatim as the HTTP Basic credential, so do not Base64-encode it again or convert it to a bearer token. </Step> <Step title="Select Inworld in messages.tts"> ```json5 { messages: { tts: { auto: "always", provider: "inworld", providers: { inworld: { voiceId: "Sarah", modelId: "inworld-tts-1.5-max", }, }, }, }, } ``` </Step> <Step title="Send a message"> Send a reply through any connected channel. OpenClaw synthesizes the audio with Inworld and delivers it as MP3 (or OGG_OPUS when the channel expects a voice note). </Step> </Steps>

Configuration options

Option	Path	Description
apiKey	messages.tts.providers.inworld.apiKey	Base64 dashboard credential. Falls back to INWORLD_API_KEY.
baseUrl	messages.tts.providers.inworld.baseUrl	Override Inworld API base URL (default https://api.inworld.ai).
voiceId	messages.tts.providers.inworld.voiceId	Voice identifier (default Sarah).
modelId	messages.tts.providers.inworld.modelId	TTS model id (default inworld-tts-1.5-max).
temperature	messages.tts.providers.inworld.temperature	Sampling temperature 0..2 (optional).

Notes

<AccordionGroup> <Accordion title="Authentication"> Inworld uses HTTP Basic auth with a single Base64-encoded credential string. Copy it verbatim from the Inworld dashboard. The provider sends it as `Authorization: Basic <apiKey>` without any further encoding, so do not Base64-encode it yourself and do not pass a bearer-style token. See [TTS auth notes](/tools/tts#inworld-primary) for the same callout. </Accordion> <Accordion title="Models"> Supported model ids: `inworld-tts-1.5-max` (default), `inworld-tts-1.5-mini`, `inworld-tts-1-max`, `inworld-tts-1`. </Accordion> <Accordion title="Audio outputs"> Replies use MP3 by default. When the channel target is `voice-note` OpenClaw asks Inworld for `OGG_OPUS` so the audio plays as a native voice bubble. Telephony synthesis uses raw `PCM` at 22050 Hz to feed the telephony bridge. </Accordion> <Accordion title="Custom endpoints"> Override the API host with `messages.tts.providers.inworld.baseUrl`. Trailing slashes are stripped before requests are sent. </Accordion> </AccordionGroup>

Related

<CardGroup cols={2}> <Card title="Text-to-speech" href="/tools/tts" icon="waveform-lines"> TTS overview, providers, and `messages.tts` config. </Card> <Card title="Configuration" href="/gateway/configuration" icon="gear"> Full config reference including `messages.tts` settings. </Card> <Card title="Providers" href="/providers" icon="grid"> All bundled OpenClaw providers. </Card> <Card title="Troubleshooting" href="/help/troubleshooting" icon="wrench"> Common issues and debugging steps. </Card> </CardGroup>