The fabric must preserve the originating interface and ID context so responses reach the correct master. It can use ID extension, remapping or other documented tracking; masters may reuse the same numeric ID at separate interfaces. Address decode needs a defined error path. Width conversion must preserve byte lanes, ordering and completion semantics if it splits a request.
Arbitration and service policies matter when multiple masters compete. AxQOS is an input to implementation-defined policy, not by itself a fairness guarantee. Review the grant policy and bounded-service assumptions before promising that CPU traffic cannot starve.
ID width: document max outstanding per master and interconnect capacity.
Document attribute preservation or permitted transformation at each bridge. A full-AXI-to-Lite conversion must respect Lite's fixed attributes rather than inventing an AxCACHE port.
Clock domain crossings: use AXI CDC FIFOs, not naive synchronizers on valid/ready.