Method run_async

src/google/adk/tools/function_tool.py:214–275

(
      self, *, args: dict[str, Any], tool_context: ToolContext
  )

  @override
  async def run_async(
      self, *, args: dict[str, Any], tool_context: ToolContext
  ) -> Any:
    # Preprocess arguments (includes Pydantic model conversion)
    args_to_call = self._preprocess_args(args)

    signature = inspect.signature(self.func)
    valid_params = {param for param in signature.parameters}
    if self._context_param_name in valid_params:
      args_to_call[self._context_param_name] = tool_context

    # Filter args_to_call to only include valid parameters for the function
    args_to_call = {k: v for k, v in args_to_call.items() if k in valid_params}

    # Before invoking the function, we check for if the list of args passed in
    # has all the mandatory arguments or not.
    # If the check fails, then we don't invoke the tool and let the Agent know
    # that there was a missing input parameter. This will basically help
    # the underlying model fix the issue and retry.
    mandatory_args = self._get_mandatory_args()
    missing_mandatory_args = [
        arg for arg in mandatory_args if arg not in args_to_call
    ]

    if missing_mandatory_args:
      missing_mandatory_args_str = '\n'.join(missing_mandatory_args)
      error_str = f"""Invoking `{self.name}()` failed as the following mandatory input parameters are not present:
{missing_mandatory_args_str}
You could retry calling this tool, but it is IMPORTANT for you to provide all the mandatory parameters."""
      return {'error': error_str}

    if isinstance(self._require_confirmation, Callable):
      require_confirmation = await self._invoke_callable(
          self._require_confirmation, args_to_call
      )
    else:
      require_confirmation = bool(self._require_confirmation)

    if require_confirmation:
      if not tool_context.tool_confirmation:
        args_to_show = args_to_call.copy()
        if self._context_param_name in args_to_show:
          args_to_show.pop(self._context_param_name)

        tool_context.request_confirmation(
            hint=(
                f'Please approve or reject the tool call {self.name}() by'
                ' responding with a FunctionResponse with an expected'
                ' ToolConfirmation payload.'
            ),
        )
        tool_context.actions.skip_summarization = True
        return {
            'error': (
                'This tool call requires confirmation, please approve or'
                ' reject.'
            )
        }