This page is very useful:
What are project roles in Jira Service Management? | Jira Service Management Cloud | Atlassian Support
However it is not clear who can change the status of the JSM ticket nor who can change the Assignee
As a Collaborator, can you change those fields, or do you need to be a licensed Agent in JSM?
We have teams that will be reviewing and completing their work items in JS. Some of these items will have be created in JS by JSM, so associated with JSM ticket.
Once the work is complete in JS work items, the person doing the work in JS would close the associated request/report in JSM.
Also, while doing their work, they may discover the JSM work item needs to be assigned to another team that does their work from JSM.