Documenting contracts REQUIRED BACKGROUND: the skill (hard rules, truth rules, style). Overview A contract document is read by a stranger who cannot see the code and is about to depend on it. Core principle: document the wire, exhaustively, with each detail at its own level; the caller's language is the wire format and domain terms, never the implementation's types. Contract surfaces are reference kind, so the core Reference rule applies: every endpoint, every field, every error. When to invoke, and not Invoke when documenting anything machines call or parse: REST and RPC endpoints, message q…