@babystack/cli

The baby command — babystack's operator & AI-agent surface. It hands you (or a coding agent) a real, seeded, disposable MySQL that persists across separate shell commands, plus a one-word reset back to the pristine baseline. Every command supports --json. Part of babystack; full picture in docs/.

Commands

| Command | Does | | --------------------- | ------------------------------------------------------------------------------------------------------------------------ | | baby doctor | Preflight: Docker reachable, Node ≥ 22, a valid babystack.config.ts, and an import-time DATABASE_URL scan of src/. | | baby wake (up) | Provision + seed a real MySQL and leave it running (detached — it outlives this command). Idempotent. | | baby home (env) | Print an eval-able DATABASE_URL for the running stack: eval "$(baby home)". | | baby reset | Reload a pristine DB from the baseline — the agent's undo. Same URL, no container re-provision. | | baby sleep (down) | Dispose this project's running stack. |

The container is discovered across invocations by a stable per-project label (a hash of the config path), so home/reset/sleep find the exact container wake started — no daemon, no state file. The minted password is recovered from docker inspect, never written to disk. (babystack's only on-disk footprint is .babystack/ — the baseline cache + a non-secret metadata sidecar.)

Run baby from your project root (where babystack.config.ts lives), or point $BABYSTACK_CONFIG at it: the project label and the cache dir are both derived from the config path, so a different cwd looks like a different project.

The agent loop

The reason the CLI exists: an AI coding agent can experiment against a real backend and undo its mess between attempts, without re-seeding from scratch.

baby wake                     # once per session: a real, seeded MySQL, left running
eval "$(baby home)"           # export DATABASE_URL for this shell

# ── the agent's attempt loop ──────────────────────────────────
#   run the app / migration / query against $DATABASE_URL
#   inspect the result
baby reset                    # wipe back to the pristine baseline, same URL — try again
#   … repeat until it gets it right …
# ──────────────────────────────────────────────────────────────

baby sleep                    # done: dispose the container

Concretely, seed one row, let the agent scribble, then reset:

$ baby wake
baby: awake — real MySQL on 127.0.0.1:54903. Run `baby home` for a connection URL.

$ eval "$(baby home)"
$ mysql "$DATABASE_URL" -e "INSERT INTO widgets (id, name) VALUES (99, 'oops')"

$ baby reset
baby: reset — the database is back to the pristine baseline.

$ mysql "$DATABASE_URL" -e "SELECT id FROM widgets"   # → only the seeded rows; id 99 is gone

Scripted / CI form (machine-readable):

baby wake --json                                  # {"ok":true,"alreadyRunning":false,"container":"…","host":"127.0.0.1","port":…}
export DATABASE_URL=$(baby home --json | jq -r '.env.DATABASE_URL')
# … agent attempt …
baby reset --json                                 # {"ok":true,"reset":true}
baby sleep --json                                 # {"ok":true,"disposed":1}

home/reset/sleep exit non-zero with nothing is awake — run \baby wake` first` when no container is up, so a script can branch on it.

Design notes

• Docker is the state. No lifecycle daemon and no PID/lock file: wake starts a detached container, later commands rediscover it by label. Nothing to leak, nothing to clean up but the container itself.
• reset == re-lease. It drops + recreates the single project database and reloads the baseline — the same fast path a Vitest worker takes per file. The DB name is stable, so your DATABASE_URL survives the reset; call home once and reset as often as you like.
• The credential boundary holds. The password is minted per container and read back from docker inspect on demand; it never touches a file. No app/DB secret from your ambient env crosses into a seed command.

Tests

• pnpm test — Docker-free unit tests (help/aliases, unknown-command, the readsEnvTooEarly heuristic).
• pnpm test:integration — the real cross-invocation flow (wake → home → reset → sleep) against a live MySQL; needs a reachable Docker engine. Set BABYSTACK_DOCKER_IT=1 locally (auto-on in CI via CI=true).