The FHIR Query Pattern extension contains the following statement in its description:

Parameters using tokens that are delimited using double-braces and the context parameters are dependent solely on the subjectType, according to the following: Patient: context.patientId, Practitioner: context.practitionerId, Organization: context.organizationId, Location: context.locationId, Device: context.deviceId.

This probably makes sense to someone who already knows what it is referring to, but is very difficult to understand for someone who isn't already familiar with this approach. Furthermore, this is only demonstrated in the last example of the CQL Module profile – which requires some digging for someone looking only at the extension definition.

Please clarify this text and/or supplement it with an inline example so that its meaning can be more easily understood.