Typically, a method like GET /api/v1/companies would have a querystring value like "showArchived=true" to allow API users to query for archived clients. This would be useful for programatically un-archiving, since there doesn't appear to be another way to get the Hudu company ID's of archived clients by company name.
For example, right now - I'm working on an onboarding automation and this is causing hangups when companies return after leaving or when being upgraded from an old package to one that uses the new automated onboarding procedure. Since I can't retrieve their old Hudu ID, and their name is already taken, I can't automatically make the company available for our support staff in Hudu.