The device’s name can be set to the deviceId or numId (i.e., without the project, location, and registry info. prepended).
string (FieldMask format)
Only updates the device fields indicated by this mask. The field mask must not be empty, contain immutable fields, or be only set by the server. Mutable top-level fields: credentials, blocked, logLevel, and metadata
A comma-separated list of fully qualified field names.
See the note at the start of this document on where to find the token.