Cleanup engine

engine/app/config.py

@@ -25,6 +25,10 @@ class Settings(BaseSettings):
     sample_rate: int = Field(default=16000, description="Audio sample rate in Hz")
     chunk_size_ms: int = Field(default=20, description="Audio chunk duration in milliseconds")
     default_codec: str = Field(default="pcm", description="Default audio codec")
+    max_audio_buffer_seconds: int = Field(
+        default=30,
+        description="Maximum buffered user audio duration kept in memory for current turn"
+    )
 
     # VAD Configuration
     vad_type: str = Field(default="silero", description="VAD algorithm type")
@@ -79,6 +83,10 @@ class Settings(BaseSettings):
         default=200, 
         description="Minimum speech duration (ms) required to trigger barge-in. Lower=more sensitive."
     )
+    barge_in_silence_tolerance_ms: int = Field(
+        default=60,
+        description="How much silence (ms) is tolerated during potential barge-in before reset"
+    )
 
     # Logging
     log_level: str = Field(default="INFO", description="Logging level")

engine/core/duplex_pipeline.py

@@ -228,21 +228,19 @@ class DuplexPipeline:
         self._is_bot_speaking = False
         self._current_turn_task: Optional[asyncio.Task] = None
         self._audio_buffer: bytes = b""
-        max_buffer_seconds = settings.max_audio_buffer_seconds if hasattr(settings, "max_audio_buffer_seconds") else 30
+        max_buffer_seconds = settings.max_audio_buffer_seconds
         self._max_audio_buffer_bytes = int(settings.sample_rate * 2 * max_buffer_seconds)
-        self._asr_start_min_speech_ms: int = (
-            settings.asr_start_min_speech_ms if hasattr(settings, "asr_start_min_speech_ms") else 160
-        )
+        self._asr_start_min_speech_ms: int = settings.asr_start_min_speech_ms
         self._asr_capture_active: bool = False
         self._pending_speech_audio: bytes = b""
         # Keep a short rolling pre-speech window so VAD transition latency
         # does not clip the first phoneme/character sent to ASR.
-        pre_speech_ms = settings.asr_pre_speech_ms if hasattr(settings, "asr_pre_speech_ms") else 240
+        pre_speech_ms = settings.asr_pre_speech_ms
         self._asr_pre_speech_bytes = int(settings.sample_rate * 2 * (pre_speech_ms / 1000.0))
         self._pre_speech_buffer: bytes = b""
         # Add a tiny trailing silence tail before final ASR to avoid
         # clipping the last phoneme at utterance boundaries.
-        asr_final_tail_ms = settings.asr_final_tail_ms if hasattr(settings, "asr_final_tail_ms") else 120
+        asr_final_tail_ms = settings.asr_final_tail_ms
         self._asr_final_tail_bytes = int(settings.sample_rate * 2 * (asr_final_tail_ms / 1000.0))
         self._last_vad_status: str = "Silence"
         self._process_lock = asyncio.Lock()
@@ -261,10 +259,10 @@ class DuplexPipeline:
 
         # Barge-in filtering - require minimum speech duration to interrupt
         self._barge_in_speech_start_time: Optional[float] = None
-        self._barge_in_min_duration_ms: int = settings.barge_in_min_duration_ms if hasattr(settings, 'barge_in_min_duration_ms') else 50
+        self._barge_in_min_duration_ms: int = settings.barge_in_min_duration_ms
+        self._barge_in_silence_tolerance_ms: int = settings.barge_in_silence_tolerance_ms
         self._barge_in_speech_frames: int = 0  # Count speech frames
         self._barge_in_silence_frames: int = 0  # Count silence frames during potential barge-in
-        self._barge_in_silence_tolerance: int = 3  # Allow up to 3 silence frames (60ms at 20ms chunks)
 
         # Runtime overrides injected from session.start metadata
         self._runtime_llm: Dict[str, Any] = {}
@@ -415,6 +413,11 @@ class DuplexPipeline:
             return self._runtime_barge_in_min_duration_ms
         return self._barge_in_min_duration_ms
 
+    def _barge_in_silence_tolerance_frames(self) -> int:
+        """Convert silence tolerance from ms to frame count using current chunk size."""
+        chunk_ms = max(1, settings.chunk_size_ms)
+        return max(1, int(np.ceil(self._barge_in_silence_tolerance_ms / chunk_ms)))
+
     async def _generate_runtime_greeting(self) -> Optional[str]:
         if not self.llm_service:
             return None
@@ -679,7 +682,7 @@ class DuplexPipeline:
                         if self._barge_in_speech_start_time is not None:
                             self._barge_in_silence_frames += 1
                             # Allow brief silence gaps (VAD flickering)
-                            if self._barge_in_silence_frames > self._barge_in_silence_tolerance:
+                            if self._barge_in_silence_frames > self._barge_in_silence_tolerance_frames():
                                 # Too much silence - reset barge-in tracking
                                 logger.debug(f"Barge-in cancelled after {self._barge_in_silence_frames} silence frames")
                                 self._barge_in_speech_start_time = None
@@ -927,9 +930,6 @@ class DuplexPipeline:
             fn = item.get("function")
             if isinstance(fn, dict) and fn.get("name"):
                 fn_name = str(fn.get("name"))
-                executor = str(item.get("executor") or item.get("run_on") or "").strip().lower()
-                if executor in {"client", "server"}:
-                    self._runtime_tool_executor[fn_name] = executor
                 schemas.append(
                     {
                         "type": "function",
@@ -943,10 +943,6 @@ class DuplexPipeline:
                 continue
 
             if item.get("name"):
-                fn_name = str(item.get("name"))
-                executor = str(item.get("executor") or item.get("run_on") or "").strip().lower()
-                if executor in {"client", "server"}:
-                    self._runtime_tool_executor[fn_name] = executor
                 schemas.append(
                     {
                         "type": "function",