diff --git a/packages/bsky/src/hydration/hydrator.ts b/packages/bsky/src/hydration/hydrator.ts
index c967908934e..8b063781754 100644
--- a/packages/bsky/src/hydration/hydrator.ts
+++ b/packages/bsky/src/hydration/hydrator.ts
@@ -567,6 +567,7 @@ const listUrisFromProfileViewer = (item: ProfileViewerState | null) => {
   if (item?.blockingByList) {
     listUris.push(item.blockingByList)
   }
+  // blocked-by list does not appear in views, but will be used to evaluate the existence of a block between users.
   if (item?.blockedByList) {
     listUris.push(item.blockedByList)
   }