diff --git a/website/docs/api/vocab.mdx b/website/docs/api/vocab.mdx
index 3b0e83d9f..57618397d 100644
--- a/website/docs/api/vocab.mdx
+++ b/website/docs/api/vocab.mdx
@@ -13,7 +13,7 @@ between `Doc` objects.
 <Infobox variant ="warning">
 
 Note that a `Vocab` instance is not static. It increases in size as texts with
-new tokens are processed.
+new tokens are processed. Some models may have an empty vocab at initialization.
 
 </Infobox>