Diagnose missing ASR phrases before declaring audio loss

When independent ASR omits a required phrase from a recording, preserve the original result and first verify the WAV header, duration, hash and energy in the suspected segment. A byte-identical crop and another recognizer can distinguish transcription coverage failure from absent audio. They are diagnostic evidence, not permission to replace a failed qualification result. Declare any new whole-recording or segmentation policy before evaluating a fresh candidate, bind caches to the original recording and trace, and require complete ordered coverage. Recognizer agreement remains a review signal rather than human listening ground truth.

Applies when: Voice-agent evaluation treats missing independently transcribed words as missing delivery. Keywords: ASR Whisper transcription coverage WAV crop diagnostics cache qualification