harden

For engineers, when a model or load is about to go live or change shape. In Claude Code this is a /truequery slash command. In Muse Code, describe the task in your own words, or load the skill with /skill truequery. In Codex the skill isn't here yet, only the checks.

/truequery harden the orders load

It runs a review first, because hardening an unchecked query bakes the bug in. Then it works through these, each with evidence or a named TODO:

1. Idempotency. Does re-running the write change nothing, and by what mechanism?
2. Late data. What's the policy, and where do out-of-order rows land?
3. Schema changes. Do new columns stay safe, and do dropped or renamed ones have a deprecation path?
4. NULL and edge guards. Are join keys, filters and division denominators handled?
5. Backfills and migrations. What's the blast radius and the rollback, and how will row counts be verified?