What an invocation amounts to, once its arguments are understood.
Splitting the decision from its effects is what makes the guidance testable:
every disclosure level, every error path and --help produce a print plan
whose text, stream and exit code can be asserted without a process.
{ readonly kind: "print"; readonly text: string; readonly stream: "stdout" | "stderr"; readonly code: number; readonly notices?: readonly string[]; }
| { readonly kind: "run"; readonly specifier: string; readonly coder: string; readonly command: CommandName; readonly arityVerified: boolean; readonly notices: readonly string[]; }