diff --git a/skills/planner/SKILL.md b/skills/planner/SKILL.md
index 266b82a..32d47bd 100644
--- a/skills/planner/SKILL.md
+++ b/skills/planner/SKILL.md
@@ -179,6 +179,17 @@ Before handing the plan off, run this checklist inline:
 5. **No commit steps:** task templates must not contain
    `git commit` instructions. Implement tasks leave work in the
    working tree.
+6. **Pin/replacement substring contiguity:** when a task ships a
+   test asserting `contains("<substring>")` (or a grep) AND another
+   task's verbatim replacement body is what must contain that
+   substring, the substring must appear *contiguously* in that
+   replacement body — no soft-wrap splitting it across two lines.
+   Two authoritative artefacts (exact pin vs. exact replacement)
+   that cannot both be applied literally is a plan defect, not an
+   implementer judgement call. This is the recurring grep/contains
+   line-wrap family (iter-revert Concern 2; iter effect-doc-honesty
+   Task 2) — scrub it here, every plan that pairs a presence-pin
+   with a verbatim text edit.
 
 Fix issues inline.