Verifiable Surfaces

Apply this skill in two complementary modes:

• Authoring mode — when creating or extending a CLI, tool, library, or service, design surfaces that can be exercised cheaply and harmlessly: --help, --dry-run, --print-config, isolated-state smoke, explicit exit codes.
• Verification mode — when editing config, CLI arg/env parsing, dotfiles, Ansible, IaC, or any rendered/generated config, walk the verification ladder until the highest harmless gate has passed.

Core Invariant

A surface that cannot be exercised cheaply and harmlessly was not actually verified. Syntax checks, type checks, and lints are necessary but not sufficient. If the program has its own loader, dry-run, or check command, run it. If it does not have one, your authoring job is to add one.