Web service calls return a normalized result value instead of raising a condition, so a caller branches on data rather than on an error handler. Transport failure, a non-success status code, and an unreadable response body are reported as three distinct outcomes. Per-host circuit breaking, retry with a transient-failure predicate, optional throttling, redacted request headers, and a success-only cache come as defaults. Many questions to one source can be asked as a single batch, where only the entries the cache is missing reach the network. Service-specific knowledge is left to the client packages built on top. The circuit breaker is the pattern described in Nygard (2018, ISBN:9781680502398).