Function synthesizeWithCartesia

apps/sim/app/api/tools/tts/unified/route.ts:489–588

(
  params: Partial<CartesiaTtsParams>
)

}

async function synthesizeWithCartesia(
  params: Partial<CartesiaTtsParams>
): Promise<{ audioBuffer: Buffer; format: string; mimeType: string }> {
  const {
    text,
    apiKey,
    modelId = 'sonic-3',
    voice,
    language = 'en',
    outputFormat,
    speed,
    emotion,
  } = params

  if (!text || !apiKey) {
    throw new Error('text and apiKey are required for Cartesia')
  }

  const requestBody: Record<string, unknown> = {
    model_id: modelId,
    transcript: text,
    language,
  }

  if (voice) {
    requestBody.voice = {
      mode: 'id',
      id: voice,
    }
  }

  const generationConfig: Record<string, unknown> = {}
  if (speed !== undefined) generationConfig.speed = speed
  if (emotion !== undefined) generationConfig.emotion = emotion
  if (Object.keys(generationConfig).length > 0) {
    requestBody.generation_config = generationConfig
  }

  if (outputFormat && typeof outputFormat === 'object') {
    requestBody.output_format = outputFormat
  }

  if (!requestBody.output_format) {
    requestBody.output_format = {
      container: 'wav',
      encoding: 'pcm_s16le',
      sample_rate: 24000,
    }
  }

  logger.info('Cartesia API request:', {
    model_id: requestBody.model_id,
    has_voice: !!requestBody.voice,
    language: requestBody.language,
    output_format: requestBody.output_format,
    has_generation_config: !!requestBody.generation_config,
  })