langchain/callbacks/tracers/stdout.py/ConsoleCallbackHandler/_on_tool_end
class ConsoleCallbackHandler:    def _on_tool_end(self, run: Run) -> None:
        crumbs = self.get_breadcrumbs(run)
        if run.outputs:
            print(
                f'{get_colored_text("[tool/end]", color="blue")} '
                + get_bolded_text(
                    f"[{crumbs}] [{elapsed(run)}] Exiting Tool run with output:\n"
                )
                + f'"{run.outputs["output"].strip()}"'
            )