Document attributes are key/value pairs that can be stored in the Illustrator document. This can be useful if, for example, the document language or a document ID is to be stored in a document. Documents can have any number of attributes.
The plugin Document Attributes only provides the user interface and is optional.
Key and value are always of data type String and must be converted if necessary (e.g. use in cScript).
With the palette Document attributes you can manually maintain the key/value pairs:
In statements such as Publishing Server calls or database statements, tags with the prefix 'xml.' are automatically replaced by the corresponding document attribute. For example, for '<xml._language>' the value of the document attribute '_language' is used if it exists, otherwise an empty string is used.
If the document attribute '_language' has the value 'eng', '<xml._language>' becomes 'eng'
For more information see here.
Document attributes are defined and queried in cScript using the functions
This functionality is analogous to the priint:comet InDesign® plugins.
The palette has the ClassID 500