Text-to-Speech

TTS runs over POST /v1/audio/speech (REST) and WS /v1/audio/speech/stream/{voice_id} (streaming). See Text-to-Speech for the full reference.

The response won’t parse as JSON

POST /v1/audio/speech returns raw audio bytes, not JSON. The Content-Type matches the requested format (e.g. audio/mpeg, audio/wav). Write the body straight to a file — don’t call .json() on it.

Voice errors / wrong or missing voice

• voice is required for ElevenLabs models and must be a valid ID for that model’s brand.
• A voice from one brand won’t work with a model from another. Browse valid IDs with GET /v1/audio/voices and filter by brand or model so you only pick voices usable with the model you call.
• Sarvam models use speaker (default anushka), not voice.

response_format rejected

Not every format is valid in every mode. wav_* formats are non-streaming only — request them with stream: false. Streaming supports mp3_*, pcm_*, ulaw_8000, alaw_8000, and opus_*.

WebSocket streaming produces no audio

The frame protocol depends on the model family:

• Standard models (Kokoro, Cartesia, …) — send input_text_buffer.append then input_text_buffer.commit; audio arrives as conversation.item.audio_output.delta (base64).
• ElevenLabs models — the first frame must be initializeConnection ({ "text": " " }), then sendText, then closeConnection ({ "text": "" }); audio arrives as AudioOutput (base64).

Audio deltas are base64 — decode before playing or writing.

Still stuck?

See the Mesh API error reference or email contact@meshapi.ai.