diff --git a/tools/generate-index.mjs b/tools/generate-index.mjs
index e3580a3..d468028 100755
--- a/tools/generate-index.mjs
+++ b/tools/generate-index.mjs
@@ -97,7 +97,7 @@ async function collectFiles(relBase = "", flat = []) {
 (async () => {
   try {
     const flat = await collectFiles();
-    // Only include sections with non-index files
+    // Sections = dirs with non-index files
     const sections = [...new Set(flat.filter(f => !f.isIndex).map(f => f.path.split("/")[0]))].sort();
     const allTags = [...new Set(flat.flatMap(f => f.tags))].sort();
     await fs.writeFile(OUT, JSON.stringify({ flat, sections, tags: allTags }, null, 2));