diff --git a/src/schemas/nostr.ts b/src/schemas/nostr.ts
index 46f68a3..4e8f917 100644
--- a/src/schemas/nostr.ts
+++ b/src/schemas/nostr.ts
@@ -32,7 +32,7 @@ const screenshotsSchema = z.array(z.object({
     'play',
   ]).optional(),
   /** https://developer.mozilla.org/en-US/docs/Web/Manifest/screenshots#sizes */
-  sizes: sizesSchema,
+  sizes: sizesSchema.optional(),
   /** Absolute URL. */
   src: z.string().url(),
   /** MIME type of the image. */