There are not documented ways to manage users as an admin in the Atlassian Cloud stack. This is a tool written in go to deactivate users from Atlassian cloud instances if they have not accessed the instance in more than 60 days.
Usage:
jiraAdmin [flags]
Flags:
-c, --cookie string jira cloud session cookie
-d, --dryrun enable dryrun
-h, --help help for jiraAdmin
-s, --site string jira cloud site id
-u, --url string jira cloud url
Cookie, site, and url are all required parameters. The cookie header can be found using developer tools looking at the entries within cookie, specifically the "cloud.session.token" entry. The site id can be derived from your site adminstration page https://<site_url>/admin/s//users. Finally the site url is just the base url of your instance https://<site_url>.
These are not documented APIs and may be subject to change at any time breaking this tool.