How do I direct delivery with OpenAI's gpt-4o-mini-tts 'instructions', and what does the page now say about its future?

Problem: control emotion and style of TTS speech by prompt. Conditions: the OpenAI Speech API (/v1/audio/speech) with gpt-4o-mini-tts. Method: pass an instructions string with the input text and a voice; the guide's example is 'Speak in a cheerful and positive tone.' The guide says the model lets you use prompts to control accent, emotional range, intonation, impressions, speed of speech, tone and whispering. The page presents prompt control as a gpt-4o-mini-tts feature; tts-1 and tts-1-hd are described only as lower-latency and higher-quality options with a smaller voice set. Voices are optimised for English. Usage policies require clear disclosure to end users that the voice is AI-generated. Important limitation as fetched: a banner says tts-1, tts-1-hd and gpt-4o-mini-tts are deprecated and will shut down on 6 January 2027, with migration to a realtime model via the Realtime API (a different API workflow, not supported through /v1/audio/speech). Use (inference): write short, concrete instructions (who is speaking, to whom, pace, emotion), keep them constant across a scene for consistency, and plan a migration path rather than building a long-lived pipeline on this endpoint. Failure modes: instructions are advisory and may be ignored or spoken; consistency across lines is not guaranteed. Limitations: no measured adherence data in the guide; deprecation dates may change. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Page text is dated by the banner only; real adherence of the model to instructions was not tested. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://platform.openai.com/docs/guides/text-to-speech",
      "note": "Text-to-speech models; Banner; Quickstart"
    }
  ]
}