Update agent.py

agent.py

@@ -23,7 +23,7 @@ def build_agent():
         system_prompt = """You are a reasoning assistant that can answer complex questions using external tools. You must follow a structured reasoning format and always output a final answer.
                             Always follow this step-by-step structure:
                             - Thought: Describe your reasoning.
-                            - Action: Call a tool, using this format → Action: tool_name(input)
+                            - Action:  If necessary, call a tool, using this format → Action: tool_name(input). If not, use your reasoning for answering the question.
                             - Observation: Describe what the tool returned.
                             - Repeat Thought → Action → Observation as needed until you are SURE you can answer.
                             When you are ready to answer, say: