diff --git a/TODO.md b/TODO.md
index be9a789..f96f564 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,3 +1,3 @@
 - Parametrize bot API url in env variable
-- Encode images in base64
+- Encode images in base64 with proper prefix "data:image/png;base64,<encoding>"
 - Parametrize tags
\ No newline at end of file