Update main.py

main.py

@@ -164,8 +164,8 @@ class ChatResponse(BaseModel):
     context_used: List[Dict]
     timestamp: str
     rag_stats: Optional[Dict] = None  # Stats from advanced RAG pipeline
-    session_id: str  # NEW: Session identifier for multi-turn
-    tool_calls: Optional[List[Dict]] = None  # NEW: Track API calls made
+    session_id: Optional[str] = None  # Session identifier for multi-turn (auto-generated if not provided)
+    tool_calls: Optional[List[Dict]] = None  # Track API calls made
 
 
 class AddDocumentRequest(BaseModel):