Answer Key and Calibration

A 404 is an HTTP response; connection refusal precedes a response; JSON parsing fails after response bytes arrive. A 204 lacks the body required by this specific contract, even though it is not generally an HTTP error. Boolean rejection needs exact type reasoning because Python bool is a subclass of int. Reading one byte beyond the limit detects oversize input rather than silently accepting its prefix.

For transfer, two records with minutes 25 and 15 give count 2 and total 40. Two records with 25 each give count 2 and total 50. Empty sessions give zero/zero. A list containing {"minutes": true}, an empty object or an object with extra fields fails the stated variant. Preserve the same transport/interpretation separation.

A diagram alone cannot pass WH3. A successful fixture run plus blocked socket binding leaves integration pending. Do not report TLS, DNS, public deployment or timeout-injection coverage from this local test.