fof-preflight

---

name: fof-preflight description: Diff-aware guardrail checker for Fear-of-Falling (FOF) changes; fails closed on raw data edits, Kxx intro/req_cols mismatches, and output discipline risks. metadata: short-description: Diff-aware FOF guardrail preflight (fail-closed).

How to use

Run from the Fear-of-Falling subproject root or repo root.

Example:

Copypython .codex/skills/fof-preflight/scripts/preflight.py

Inputs

• Git working tree diff (git diff --name-only --diff-filter=ACMRTUXB).
• Kxx R scripts under Fear-of-Falling/R-scripts/ (or R-scripts/).
• Policy sources: Fear-of-Falling/CLAUDE.md, Fear-of-Falling/QC_CHECKLIST.md.

Outputs

• Console summary with PASS/WARN/FAIL.
• Exit code 0 only if no FAIL conditions are found.

Failure modes

• Not a git repo or diff fails.
• Any change under data/ or data/external/.
• Kxx .R scripts missing the standard intro/Required vars block.
• Required vars list cannot be parsed unambiguously.
• req_cols <- c(...) cannot be parsed or has multiple definitions.
• Required vars list does not match req_cols 1:1.
• Suspicious outputs/ usage not under R-scripts/<script>/outputs/.

Safety/guardrails

• FAIL CLOSED: if a rule cannot be verified, the script exits 1 with context.
• No external APIs or network calls.
• Does not modify data or outputs.
• If other raw-data root paths are discovered in docs/scripts, do not add them without explicit user confirmation (fail closed and request clarification).

Sources: Fear-of-Falling/CLAUDE.md, Fear-of-Falling/QC_CHECKLIST.md.