Handling failures REQUIRED BACKGROUND: the skill. Overview A swallowed error is a bug with its evidence destroyed. Core contract: every failure path does exactly one of three things, and all three are loud. A system that looks healthy while serving wrong data is worse than one that crashes. The contract Every catch and failure path either: 1. Logs at WARN or ERROR and rethrows , or 2. Logs and returns a TYPED failure the caller must handle (a result type, a sealed error, a status the compiler or contract forces downstream code to acknowledge), or 3. Logs and enters an explicitly documented de…