Update app.py

app.py

@@ -46,19 +46,16 @@ def navigate(screenshot, task: str, platform: str, history):
 
     # ───────────────────── normalise history input ──────────────────────────
     messages=None
-    if history in (None, ""):
-        history_list = []
+  
+    if isinstance(history, str):
+        try:
+            messages= ast.literal_eval(history)
+        except Exception as exc:
+            raise ValueError("`history` must be a JSON/Python list: " + str(exc))
     else:
-        if isinstance(history, str):
-            try:
-                messages= ast.literal_eval(history)
-            except Exception as exc:
-                raise ValueError("`history` must be a JSON/Python list: " + str(exc))
-        else:
-            messages = history
-
-        if not isinstance(history_list, list):
-            raise ValueError("`history` must be a list of messages.")
+        messages = history
+
+        
 
     # ─────────────────────────── model forward ─────────────────────────────
     text = processor.apply_chat_template(