| # Model Backends | |
| - Qwen2.5-VL-7B-Instruct: real frame-conditioned invocations. Only direct or safely repaired structured JSON that passes field validation is accepted. | |
| - CLAP: real audio-tagging scores retained for ProactiveAVInteraction. | |
| - WhisperX small: real segment transcription. Empty no-speech results are explicitly marked `asr_status=no_speech`; timestamps are segment-level. | |
| - OCRScreenGrounding: deterministic generator ground truth, not OCR-model inference. | |
| - Piper `en_US-lessac-medium`: deterministic materialization for the internal speech package. Generated speech is documented as synthetic. | |