langchain/evaluation/agents/trajectory_eval_chain.py/TrajectoryEvalChain/_tools_description
class TrajectoryEvalChain:    def _tools_description(self) -> str:
        return "\n\n".join(
            [
                f"""Tool {i}: {tool.name}
Description: {tool.description}"""
                for i, tool in enumerate(self.agent_tools, 1)
            ]
        )