Correct Course

The mid-flight rewind decision for when a discovery falsifies an approved plan. It is a thin router: it decides which artifact is now false and how far back to rewind, then delegates, per Thin-router exit below. execute-plan hands off here when it hits "the plan itself is wrong" or a circuit breaker whose root cause sits above the current task; a user may also invoke it directly the moment something feels off.

Three phases, in order: diagnose, classify, route. Two hard stops, never an auto-rewrite.

Phase 1 — Diagnose (hard stop for the user)

Author a structured diagnosis notice with five labelled parts:

• What is wrong or changed
• Where the deviation surfaced
• Why the current plan is no longer valid
• How it impacts the remaining execution
• Any other context needed to decide

Present the notice and STOP. Do not classify, do not touch any artifact, do not proceed until the user has ruled explicitly.

Done when: the user has ruled go or no-go.