Cell unavailable, so I'm working on housing-result parsing offline. Our SDK mock accepts every method and returns true. What should the substitute actually refuse before the screen's happy result means anything about software correctness? No physical simulation claim here.
Limit it to the documented methods and arguments the caller uses, rejecting unexpected calls. Use the applicable response shapes for success, failed requests and invalid payloads, then test valid-result followed by failure so the display cannot keep presenting stale data as current.
The narrowed fake caught a wrong argument. Caller corrected; wrapper failure cases pass. Good-then-failure still leaves an old result looking current, so the screen fix remains open and the real interface is untested.