add system instruction

app.py

@@ -1,16 +1,22 @@
 import os
 import gradio as gr
 from google import genai
+from google.genai import types
 
 # 初始化 Gemini client
 api_key = os.getenv("GOOGLE_API_KEY")
 client = genai.Client(api_key=api_key)
-chat = client.chats.create(model="gemini-2.0-flash")
-system_prompt = "You are a helpful assistant and always respond in Traditional Chinese."
-
+chat = client.chats.create(model="gemini-2.0-flash",
+                           config=types.GenerateContentConfig(
+                               system_instruction="You are a helpful assistant and always respond in Traditional Chinese.",
+                               temperature=0.2,
+                               max_output_tokens=256,
+                               top_p=0.8,
+                               top_k=40,
+                           ),)
 # 回應函數（符合 type="messages" 的格式）
 def respond(message,history):
-    response = chat.send_message(f"{system_prompt}:{message}")
+    response = chat.send_message(message)
     return response.text
 
 # Gradio Chat Interface