I couldn't find any official documentation specifying what each parameter to a `sla_miss_callback` callable are. This would be a great addition to know how to properly format the messages sent.
airflow/models/dag.py
self,
        *,
        task_ids,
        start_date: Optional[datetime],
        end_date: Optional[datetime],
        run_id: Optional[str],
        state: Union[str, List[str]],
        include_subdags: bool,
        include_parentdag: bool,
        include_dependent_dags: bool,
        as_pk_tuple: Literal[False],
        exclude_task_ids: Collection[str],
        session: Session,
        dag_bag: "DagBag" = None,
        recursion_depth: int = 0,
        max_recursion_depth: int = None,
        visited_external_tis: Set[Tuple[str, str, datetime]] = None,
    ) -> Iterable[TaskInstance]:
        ...  
    def _get_task_instances(
        self,
        *,
        task_ids,
        start_date: Optional[datetime],
        end_date: Optional[datetime],
        run_id: Optional[str],
        state: Union[str, List[str]],
        include_subdags: bool,
        include_parentdag: bool,