diff --git a/skills/diagram-design/assets/template-dark.html b/skills/diagram-design/assets/template-dark.html
index 04e2f35..dcc1014 100644
--- a/skills/diagram-design/assets/template-dark.html
+++ b/skills/diagram-design/assets/template-dark.html
@@ -58,6 +58,7 @@
     <p class="eyebrow">[Type] · Diagram Design</p>
     <h1>[Diagram title]</h1>
 
+    <!-- Replace [diagram-slug] with a unique slug for this diagram before export. -->
     <svg viewBox="0 0 1000 600" xmlns="http://www.w3.org/2000/svg" role="img" aria-labelledby="[diagram-slug]-title [diagram-slug]-desc">
       <title id="[diagram-slug]-title">[Diagram title]</title>
       <desc id="[diagram-slug]-desc">[One sentence describing what the diagram shows]</desc>
diff --git a/skills/diagram-design/assets/template-full.html b/skills/diagram-design/assets/template-full.html
index 7c4e95e..840a9ce 100644
--- a/skills/diagram-design/assets/template-full.html
+++ b/skills/diagram-design/assets/template-full.html
@@ -175,6 +175,7 @@
 
     <!-- Main Diagram -->
     <div class="diagram-container">
+      <!-- Replace [diagram-slug] with a unique slug for this diagram before export. -->
       <svg viewBox="0 0 1000 700" xmlns="http://www.w3.org/2000/svg" role="img" aria-labelledby="[diagram-slug]-title [diagram-slug]-desc">
         <title id="[diagram-slug]-title">[Diagram title]</title>
         <desc id="[diagram-slug]-desc">[One sentence describing what the diagram shows]</desc>
diff --git a/skills/diagram-design/assets/template-terminal.html b/skills/diagram-design/assets/template-terminal.html
index 2253078..efc271d 100644
--- a/skills/diagram-design/assets/template-terminal.html
+++ b/skills/diagram-design/assets/template-terminal.html
@@ -128,6 +128,7 @@
         </p>
         <h1>[Diagram title]</h1>
 
+        <!-- Replace [diagram-slug] with a unique slug for this diagram before export. -->
         <svg viewBox="0 0 1000 600" xmlns="http://www.w3.org/2000/svg" role="img" aria-labelledby="[diagram-slug]-title [diagram-slug]-desc">
           <title id="[diagram-slug]-title">[Diagram title]</title>
           <desc id="[diagram-slug]-desc">[One sentence describing what the diagram shows]</desc>
diff --git a/skills/diagram-design/assets/template.html b/skills/diagram-design/assets/template.html
index c0b2d69..6c393d3 100644
--- a/skills/diagram-design/assets/template.html
+++ b/skills/diagram-design/assets/template.html
@@ -58,6 +58,7 @@
     <p class="eyebrow">[Type] · Diagram Design</p>
     <h1>[Diagram title]</h1>
 
+    <!-- Replace [diagram-slug] with a unique slug for this diagram before export. -->
     <svg viewBox="0 0 1000 600" xmlns="http://www.w3.org/2000/svg" role="img" aria-labelledby="[diagram-slug]-title [diagram-slug]-desc">
       <title id="[diagram-slug]-title">[Diagram title]</title>
       <desc id="[diagram-slug]-desc">[One sentence describing what the diagram shows]</desc>