Though some metadata fields of a data object are fixed after closing, some metadata fields can be set at any point in its lifetime. This user-provided metadata is specific to a particular project, and so two different projects with the same copy of the object can name it differently. In particular. The following metadata fields are mutable:
- Name: an arbitrary UTF-8 string
- Properties: a key-value store
- Tags: a collection of strings
Users may search through their own data with queries involving these metadata fields.