I know unsupported payloads need an explicit failure. This FR10 replacement environment returns a container instead of the old status value, and our availability display still finds a plausible answer in failed requests. Which path needs checking next?
Trace one retained failed response through the wrapper to the display, with the imported version identified; knowing the desired failure state does not show whether the adapter or a later fallback is replacing it
Adapter returns unavailable correctly for the saved failure. The display handler catches that and substitutes its configured default status. So the false reading comes after decoding, not from a mysterious numeric field
That would be worth separating from retained history too, Ada, because a default has never been observed while a last valid value was observed at some earlier time
Yes, startup uses it too. We've removed that fallback. Initial state is no observation; failures show current information unavailable, with any earlier reading labelled as history rather than substituted as the answer
And use the installed-version success and failure examples rather than making both environments obey one invented response shape; the shared display meaning can stay consistent while each supported adapter interprets its own contract
Both supported adapters and the normal display now pass startup, good-then-failed, good-then-malformed and reopening with history. The read-only controller comparison also completed. No fabricated default reading returns after any of those cases