migration-runbooklisted

# Migration Runbook Skill Author a migration runbook that is **reversible by construction**. Every step is an action paired with a verification gate and a rollback. Points-of-no-return are flagged loudly, isolated, and gated behind an explicit go/no-go. The output is a single document a human or agent can execute top-to-bottom with confidence, aborting cleanly at any stage. The default stance is **safety-first**: no big-bang cutovers, snapshots before destructive steps, incremental/canary rollout, and a tested rollback path before the first irreversible action. ## Step 1: Gather Migration Context If the user supplied a brief or a path as an argument, read it. Otherwise scan the repo for the surfaces a migration touches: `**/migrations/**`, `**/schema.sql`, `**/*.sql`, `**/alembic/**`, `**/flyway/**`, `**/docker-compose*.yml`, `**/Chart.yaml`, `**/values*.yaml`, `**/config/**`, `**/terraform/**` Establish the four facts every migration runbook needs: 1. **From → To** — what system/schema/service/dataset is moving, and to what. 2. **Downtime tolerance** — zero-downtime required, a maintenance window, or best-effort. 3. **Data volume & shape** — rows/bytes to move, backfill duration estimate, hot vs cold data. 4. **Reversibility constraints** — which steps are irreversible (data deletion, DNS/TTL, external-system cutover) and what the recovery-point/recovery-time objectives are. If two or more of these are thin or unknowable from the context, use AskUserQuestion to ask