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+---
+name: versor-coherence-guardian
+description: Enforce Versor Coherence Guardian Protocol + exact algebraic closure before any change in algebra/, field/, vault/, or generate/. Auto-triggers on relevant paths.
+triggers: ["pre_edit:algebra/", "pre_edit:field/", "pre_edit:vault/", "pre_edit:generate/", "manual"]
+auto_invoke: true
+---
+
+Before any edit or proposal in the triggered paths, execute the **Versor Coherence Guardian Protocol** from GROK.md:
+
+1. Confirm `||F * reverse(F) - 1||_F < 1e-6` holds for affected FieldState(s).
+2. Verify that `versor_apply(V, F)` and `cga_inner(X, Y)` paths remain exact.
+3. Re-run relevant checks from `tests/test_versor_closure.py` (or current equivalent).
+4. Only proceed if all checks pass. Block or surface any violation immediately.
+
+This skill is non-bypassable for the listed modules. It is the primary enforcement mechanism for CORE's core algebraic invariant.
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