diff --git a/23.md b/23.md
index 54009661..a3117b8a 100644
--- a/23.md
+++ b/23.md
@@ -21,7 +21,7 @@ For the date of the last update the `.created_at` field should be used, for "tag
 Other metadata fields can be added as tags to the event as necessary. Here we standardize 4 that may be useful, although they remain strictly optional:
 
 - `"title"`, for the article title
-- `"image"`, for an image to be shown along with the title
+- `"image"`, for a URL pointing to an image to be shown along with the title
 - `"summary"`, for the article summary
 - `"published_at"`, for the timestamp in unix seconds (stringified) of the first time the article was published