I am wondering there is a way to create sub-tasks automatically when issue created.
For example, I create a custom Standard Issue Type, XXX, and Sub-tasks Issue Type YYY and ZZZ. When I create a issue with type XXX, then two sub-tasks with respective issue type YYY and ZZZ will be created automatically.
You could so this easily using Jira Scripting Suite by using post function on issue creation transition on the project’s workflow. Sample code: