Hi Carl,
We're typically referring to our cloud FHIR or authorization log files. The X-Request-Id and Cerner-Correlation-Id headers we send in the response allow us to track down specific instances of errors so that we can help troubleshoot issues (especially when apps are first integrating in our sandbox).
We also try to return something meaningful in the error responses of the servers, but not all apps (or libraries) capture the response bodies or response headers and show it. We're also improving the responses sent back to apps for FHIR in R4 (more operationOutcomes will be sent back if there's an error).
Since FHIR is a Cerner managed, cloud hosted, multi-tenant environment, we provide the support and management for the cloud services. We do expose Lights On to clients for views of what apps are using FHIR, which resources they use, and how much usage is occurring. As you note, the audit logs also have some of that information (though it's meant/structured more for HIPAA type reports and audits).
What type of information are you wanting to get to? Is this for troubleshooting apps you are developing? Or another use case?
Regards,
Jenni