Speech generation - NinjaChat Developers

Use your API key to generate narration, ad reads or spoken translations. For Claude or another agent, use MCP voiceovers.

Generate an MP3

cURL

curl --fail-with-body https://www.ninjachat.ai/api/v1/audio/speech \
  -H "Authorization: Bearer $NINJACHAT_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"tts-1-hd","input":"Welcome to your next idea.","voice":"nova","response_format":"mp3"}' \
  --output narration.mp3

A successful response contains audio bytes, not a JSON URL. Errors return JSON. Response headers include X-Request-ID and X-NinjaChat-Cost-USD.

Options

Parameter	Values
`model`	Required: `tts-1` or `tts-1-hd`.
`input`	Required: 1–4,096 characters.
`voice`	Required: `alloy`, `ash`, `coral`, `echo`, `fable`, `onyx`, `nova`, `sage` or `shimmer`.
`response_format`	`mp3` (default), `opus`, `aac`, `flac`, `wav` or `pcm`.
`speed`	0.25–4; default 1.

The REST API supports more audio formats than the MCP tool. Audio charges use your Developer Balance and are based on script length.