Gen-Plan

Contract

Scope: operate in the repo root only; manage files named plan-N.md where N is an integer.
Output location is fixed: write plan-N.md to the current repo root directory only.
Never write plan.md, PLAN.md, or any non-plan-N.md filename.
Never write outside the repo root. Prohibited examples include ~/Downloads, $HOME, absolute paths, or sibling directories.
If any instruction or path suggests writing outside the repo root, stop and ask for clarification.
Define N as the maximum numeric suffix among files matching plan-(\d+).md (ignore non-matching filenames, including legacy plan-N-E.md / plan-N-R.md).
If any matching file has N > 5: do nothing; reply exactly: "Plan is ready."
If plan-5.md exists (case-insensitive): do nothing; reply exactly: "Plan is ready."
If no matching plan-(\d+).md exists: run the clarification flow, then create plan-1.md.
Otherwise: create plan-(N+1).md. Source plan markdown: plan-N.md.
When loading plan markdown from a source file, insert the full contents of plan-N.md at the <INCLUDE CONTENTS OF PLAN FILE> placeholder in the plan template.
Never overwrite an existing target file; stop and report the conflict.
Ask questions only when unresolved judgment calls block the next iteration.