This is the Tidepool data type for a variety of events that can occur on diabetes devices, including both insulin pumps and continuous glucose monitors. As a type, it is essentially a "grab bag" of miscellaneous sub-types, where each sub-type has its own data model that often differs widely from sub-type to sub-type.
Along with Tidepool's release of "Bootstrapping to UTC" (BtUTC), we introduced the current device event model to reflect that this group of sub-types brings together miscellaneous events that are user-initiated or surfaced to the user.
These sub-types are not device metadata that may be user-invisible (or irrelevant to the user), such as device model and serial numbers, etc.