@何泳麟 Thanks for reaching out to us, there is no that kind of parameters currently in Text to Speech API, may I know more details about your scenario so that I can forward this feedback to product team for discussion? Is that for any specific cost management purposes?
One thing we can do now, you may consider leverage 'description' parameter in SSML to do the same thing, but I am not pretty sure if that fit your project and how you want to use this data.
But it is not that convenient - https://learn.microsoft.com/en-us/azure/ai-services/speech-service/speech-synthesis-markup
If you can share more details, I am happy to discuss further possibilities.
I hope this helps.
Regards,
Yutong
-Please kindly accept the answer if you feel helpful to support the community, thanks a lot.