# Rollback and alerts

`GET /health` answers `ok` when the Worker is running. `GET /ready` answers 200 only when a Solana wallet, `MAIL_FROM`, and `RESEND_API_KEY` are set. It returns booleans, never the values.

Watch Workers logs for `mail_sent`, `mail_retry`, and `mail_failed_permanent`. A permanent mail failure means five attempts did not send. Fix the Resend secret or sender, then the next cron drains a still-pending job. A job already marked failed stays failed.

To undo a Worker deploy, run `npx wrangler rollback`. To undo D1 data, restore that database with D1 Time Travel in the Cloudflare dashboard, then confirm `/ready` again. Do not enable R2 or the Workers Paid plan as part of recovery.