Is it possible to insert a script into the transition description?

Question

JIRA

Challenge:
There is a transition in a JIRA business process from one status to another. It is necessary that at this transition either the initiation of the creation of a subtask, or the setting of the field value, in general, is a non-trivial task.
Question:
Can this be solved by writing a script, for example, in the transition description? And if so, what literature would you recommend reading on this topic?

PS It is advisable to get away from paid plugins.

Answer 1

https://marketplace.atlassian.com/apps/373929/sil-...
Install, it's free. And start learning SIL markup. There are no guarantees that the engine will not become paid in the future. But scripting in "bare" JIRA is not supported
"There is a transition from one status to another in the JIRA business process. It is necessary that this transition either initiates the creation of a subtask or sets the value of a field, in general, a non-trivial task."
Specifically, in this case, clearly something can be done using the free JIRA Automation Lite. The built-in tool for the simplest scripting (automation, to be more precise) is only JIRA Service Desk