curl --request POST \
  --url https://api.omnimux.ai/v1/audio/speech \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "model": "gpt-4o-mini-tts",
  "input": "你好！欢迎使用 OmniMux 语音合成服务。",
  "voice": "alloy"
}' \
  --output speech.mp3

{
  "error": { "message": "Invalid request", "type": "invalid_request_error", "code": "bad_request" }
}

{
  "error": { "message": "Invalid token", "type": "authentication_error", "code": "unauthorized" }
}

{
  "error": {
    "message": "Insufficient quota. Please top up your account.",
    "type": "insufficient_quota",
    "code": "insufficient_quota"
  }
}

{
  "error": { "message": "Rate limit exceeded", "type": "rate_limit_error", "code": "rate_limit_exceeded" }
}

{
  "error": { "message": "Internal server error", "type": "server_error", "code": "internal_error" }
}