Update backend/main.py

backend/main.py

@@ -191,8 +191,13 @@ def extract_protocol(client: Groq, pdf_path: str, filename: str) -> dict:
             "reagents, antibodies, and equipment settings.\n\nPAPER TEXT:\n" + paper_text
         }
     ]
-    raw    = call_groq_with_backoff(client, messages)
-    result = parse_json_response(raw)
+    raw = call_groq_with_backoff(client, messages)
+
+    try:
+        result = parse_json_response(raw)
+    except Exception as e:
+        raise ValueError(f"Invalid JSON returned by LLM: {str(e)}")
+
     result["_filename"] = filename
     return result