Retry logic is being implemented:
flutter/cocoon#683

It would be good to apply it to all other existing APIs which are suitable. Some examples:
https://github.com/flutter/cocoon/blob/master/app_dart/lib/src/request_handlers/append_log.dart#L64
https://github.com/flutter/cocoon/blob/master/app_dart/lib/src/request_handlers/push_build_status_to_github.dart#L92
https://github.com/flutter/cocoon/blob/master/app_dart/lib/src/request_handlers/reserve_task.dart#L69
https://github.com/flutter/cocoon/blob/master/app_dart/lib/src/request_handlers/refresh_github_commits.dart#L286