Use the answer_prefix functionality in the interactive_document for f…

…orcing answer to start with a prefix

PiperOrigin-RevId: 590918604
Change-Id: Ifb1c26686648647ae01412183edd66e6212bc226

concordia/components/agent/characteristic.py

@@ -104,7 +104,6 @@ def update(self) -> None:
         f"How would one describe {self._agent_name}'s"
         f' {self._characteristic_name} given the following statements? '
         f'{self._extra_instructions}'
-        f'Start the answer with "{self._agent_name} is"'
     )
     if self._clock_now is not None:
       question = f'Current time: {self._clock_now()}.\n{question}'
@@ -113,6 +112,7 @@ def update(self) -> None:
         '\n'.join([question, f'Statements:\n{mems}']),
         max_characters=3000,
         max_tokens=1000,
+        answer_prefix=f'{self._agent_name} is ',
     )
 
     self._last_chain = prompt