Placing checkpoints where workflow errors become costly

Add a checkpoint after parsing, before irreversible actions, and before sharing the final output. Each checkpoint should have a concrete pass condition, a failed-state destination, and an owner.

Do not ask a human to recheck every trivial step; focus on data loss, privacy, money, and externally visible mistakes. Test one forced failure to confirm the workflow stops or routes it correctly, then verify retries do not duplicate work.

Which step is hardest to undo?