Context
All palceholders in the AccPack - Generic Placeholder evaluate the document metadata _language and _country to determine the context.
The rule that determines the value of the Context is set to useDocumentVariable and will expect the Keys to be available during the execution of the placeholder.
If this should apply globally for your priint:comet project, you can check that this behavior is correctly set inside the global project settings.

Example of the Usage
In the following example screenshots the language and country context are set to apply from document metadata (document variable)
Country context supported:

Language context supported:

Further Reading
Check the documentation of Context Criteria for more details.