edit

app.py

@@ -27,10 +27,24 @@ def load_model():
     model.eval()
     print("Model loaded.")
 
+def normalize_content(msg):
+    """Convert list content to string (Gradio may pass content as a list)."""
+    if isinstance(msg.get("content"), list):
+        parts = []
+        for item in msg["content"]:
+            if isinstance(item, dict) and "text" in item:
+                parts.append(item["text"])
+            elif isinstance(item, str):
+                parts.append(item)
+        return {"role": msg["role"], "content": " ".join(parts)}
+    return msg
+
 def chat_response(message, history):
     load_model()
 
-    messages = history + [{"role": "user", "content": message}]
+    # Normalize history: convert any list content to plain strings
+    clean_history = [normalize_content(m) for m in history]
+    messages = clean_history + [{"role": "user", "content": message}]
 
     text = tokenizer.apply_chat_template(
         messages,