# OpenAiAudioSpeechModel -- MOCK server

speech.call(String) with every default:
  request json : {"input":"Three action items.","model":"gpt-4o-mini-tts","voice":"alloy","response_format":"mp3","speed":1.0}
  response     : 20310 bytes

with TextToSpeechPrompt and options:
  request json : {"input":"Rahul: fix the login timeout bug.","model":"gpt-4o-mini-tts","voice":"coral","instructions":"Calm, like a project manager reading notes.","response_format":"wav","speed":1.1}
  response     : 35244 bytes, starts with RIFF

input of 5000 characters -> BadRequestException: 400: mock: the maximum length of input is 4096 characters, got 5000
