What problem does it solve? Hand-done edits, migrations, and analyses cannot be re-verified without redoing them, forcing reviewers to trust the author instead of checking the work. This Skill instructs the agent to build a deterministic tool that performs or proves the work, turning "trust me" into "run this". ## Core Features & Use Cases - Lever-First Workflow: Do the first unit by hand to learn the recipe, then build a codemod, script, or generator and prove it by diffing against the hand-done version. - Deterministic Over Fan-Out: Prefer a single-pass tool over delegating repetitive hand-application to subagents; when delegating, write the recipe as a shared skill outside the delegates' write scope. - Reviewable Artifacts: Produce a committed, rerunnable artifact (codemod, generator, sqlite dump query, or verification check) that reviewers can rerun to validate the work. - Use Case: When migrating hundreds of files to a new API, write a codemod, verify it against one hand-edited file, run it across the codebase, and commit the script so the migration can be rerun later. ## Quick Start Apply the build-the-lever principle to this migration task by writing a rerunnable codemod instead of editing each file by hand.
