When requests to Step Function fail, Workflow Service performs exponential backoff retries to notify Step Function service. Number of retries = 3 The total duration of all attempts doesn't exceed 10 seconds.

Script
{
  "defaultTaskList": { "name": "_defaultTaskList" },
  "defaultTaskPriority": "0",
  "defaultTaskScheduleToStartTimeout": "NONE",
  "defaultTaskScheduleToCloseTimeout": "60",
  "defaultTaskStartToCloseTimeout": "120",
  "defaultTaskHeartbeatTimeout": "NONE"
}