fix: make --input optional when --check-model is used

scripts/generate_scene_descriptions.py

@@ -321,7 +321,7 @@ def main():
     parser = argparse.ArgumentParser(
         description="Auto-generate scene descriptions from media assets using vision AI"
     )
-    parser.add_argument("--input", "-i", required=True, help="Input directory with media files")
+    parser.add_argument("--input", "-i", default="", help="Input directory with media files")
     parser.add_argument("--output", "-o", default="training-data/scene-descriptions-auto.jsonl")
     parser.add_argument("--model", "-m", default="gemma4:latest", help="Ollama model name (auto-detects if empty)")
     parser.add_argument("--ollama-url", default="http://localhost:11434")
@@ -354,6 +354,11 @@ def main():
                   file=sys.stderr)
             sys.exit(1)
 
+    # Validate input
+    if not args.input:
+        print("Error: --input is required (unless using --check-model)", file=sys.stderr)
+        sys.exit(1)
+
     # Scan and process
     media_files = scan_media(args.input)
     print(f"Found {len(media_files)} media files", file=sys.stderr)