Right, most of the APIs used are documented, but https://slack.com/api/users.admin.setInactive is not. There are some unofficial docs: https://github.com/ErikKalkoken/slackApiDoc/blob/master/user...
Otherwise APIs used are documented: https://api.slack.com/methods/files.delete https://api.slack.com/methods/chat.delete https://api.slack.com/methods/search.files https://api.slack.com/methods/search.messages
To be clear: NOT recommending Slack. Just mentioning that we also have issues and some tooling has helped, the tools could use more docs but they're pretty simple and open source FWIW.