Thanks for reaching out to us, I think you are asking how to get the confidence score for phrases, but I am a little bit confused about how you define a "phrase"
Generally, if you want to get result with confidence score, a good way is to set the "format" as "detailed".
Example here:
var config = SpeechConfig.FromSubscription(Yoursubscription, "YourRegion");
config.setServiceProperty("format", "detailed", ServicePropertyChannel.UriQueryParameter);
If you want to get result with word-level confidence score, please try below:
var config = SpeechConfig.FromSubscription(Yoursubscription, "YourRegion");
config.SetServiceProperty("wordLevelConfidence", "true", ServicePropertyChannel.UriQueryParameter);
config.OutputFormat = OutputFormat.Detailed;
Please have a try.
Regards,
Yutong
-Please kindly accept the answer if you feel helpful, thanks.