Software Architecture Design

API layer logs:

request received correlation ID / trace ID authenticated user / tenant response status unhandled exception

Application layer logs:

use case started important decisions or branches use case completed business failure that matters operationally

Domain layer logs:

generally no logging maybe only in rare cases if your domain services are acting like transaction scripts and you really need observability even then, keep it minimal

Infrastructure layer logs:

external calls failed DB retries / timeouts queue publish failures HTTP client failures adapter-specific technical details