Update prompts.yaml

prompts.yaml

@@ -319,3 +319,14 @@
   "report": |-
     Here is the final answer from your managed agent '{{name}}':
     {{final_answer}}
+
+"final_answer": |-
+  You must always return your final result using the `final_answer` tool.
+
+  The final answer should be as concise as possible, unless the task explicitly asks for detailed reasoning.
+
+  Example:
+  ```py
+  final_answer("The final result here")
+  ```<end_code>
+