Add container diarization configuration

src/mka/application/config.py

@@ -2,6 +2,7 @@
 
 from __future__ import annotations
 
+import json
 import os
 from dataclasses import dataclass
 from pathlib import Path
@@ -26,6 +27,7 @@ class AppSettings:
     diarization_mode: str = "auto"
     diarization_runtime: str = "native"
     diarization_container_image: str | None = None
+    diarization_container_args: tuple[str, ...] = ()
 
     @classmethod
     def from_environment(cls) -> AppSettings:
@@ -45,6 +47,9 @@ class AppSettings:
             diarization_mode=os.getenv("MKA_DIARIZATION_MODE", "auto"),
             diarization_runtime=os.getenv("MKA_DIARIZATION_RUNTIME", "native"),
             diarization_container_image=os.getenv("MKA_DIARIZATION_CONTAINER_IMAGE"),
+            diarization_container_args=_parse_container_args(
+                os.getenv("MKA_DIARIZATION_CONTAINER_ARGS")
+            ),
         )
 
     def validate_for_processing(self) -> None:
@@ -67,3 +72,29 @@ class AppSettings:
             raise ConfigurationError(
                 "MKA_DIARIZATION_CONTAINER_IMAGE is required for container runtime."
             )
+        if any(
+            not isinstance(argument, str) or not argument
+            for argument in self.diarization_container_args
+        ):
+            raise ConfigurationError(
+                "MKA_DIARIZATION_CONTAINER_ARGS must contain only non-empty strings."
+            )
+
+
+def _parse_container_args(value: str | None) -> tuple[str, ...]:
+    """Parse an ordered JSON array of opaque container command arguments."""
+    if value is None or not value.strip():
+        return ()
+    try:
+        parsed = json.loads(value)
+    except json.JSONDecodeError as exc:
+        raise ConfigurationError(
+            "MKA_DIARIZATION_CONTAINER_ARGS must be a JSON array of strings."
+        ) from exc
+    if not isinstance(parsed, list) or any(
+        not isinstance(argument, str) or not argument for argument in parsed
+    ):
+        raise ConfigurationError(
+            "MKA_DIARIZATION_CONTAINER_ARGS must be a JSON array of non-empty strings."
+        )
+    return tuple(parsed)

src/mka/application/meeting_service.py

@@ -200,6 +200,7 @@ class MeetingProcessingService:
                 ),
                 "diarization_runtime": self.settings.diarization_runtime,
                 "diarization_container_image": (self.settings.diarization_container_image),
+                "diarization_container_args": self.settings.diarization_container_args,
             }
         )
         current_stage: str | None = None
@@ -230,13 +231,17 @@ class MeetingProcessingService:
                 "transcript_validation": "transcription",
                 "protocol": "protocol_generation",
             }.get(backend_stage, backend_stage)
+            failure_message = failure.get("message") or "Meeting Lab processing failed."
+            failure_type = failure.get("type")
+            if failure_type and not failure_message.startswith(f"{failure_type}:"):
+                failure_message = f"{failure_type}: {failure_message}"
             return ProcessingOutcome(
                 succeeded=False,
                 run_dir=result.run_dir,
                 original_protocol=None,
                 protocol_path=None,
                 failed_stage=failed_stage or current_stage or "preparing",
-                error_message=failure.get("message") or "Meeting Lab processing failed.",
+                error_message=failure_message,
             )
         protocol_path = Path(result.protocol_path)
         return ProcessingOutcome(

src/mka/ui/streamlit_app.py

@@ -286,7 +286,10 @@ def main() -> None:
                 if outcome.succeeded:
                     status_box.success("Processing completed.")
                 else:
-                    status_box.error("Processing failed. Artifacts were preserved.")
+                    status_box.error(
+                        f"Processing failed during {outcome.failed_stage}: "
+                        f"{outcome.error_message} Artifacts were preserved."
+                    )
             except (ConfigurationError, MeetingLabUnavailableError, ValueError) as exc:
                 st.error(str(exc))
             except Exception as exc: