diff --git a/CLAUDE.md b/CLAUDE.md
index 008f7a3b..4d6990f9 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -217,4 +217,6 @@ with each other.
   churn, works uniformly regardless of whether the doc already had a
   clean boundary. Caveat: it only collapses in a rendered browser —
   reading the file as raw text (`cat`, the Read tool) shows everything,
-  same as today.
+  same as today. Also: the `<summary>` line itself isn't markdown-
+  processed — backticks render as literal characters, not styled code
+  — so keep summary text plain prose, no inline-code formatting.