diff --git a/README.md b/README.md
index cbddaaf..27c4711 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,7 @@ the following environment variables are required:
 - `GITHUB_WEBHOOK_SECRET`: the secret you chose when you created the json webhook
 - `DISCORD_WEBHOOK`: the regular discord webhook url
 - `DISCORD_BOT_WEBHOOK`: the discord webhook url for bot-authored events
+- `DISCORD_ERROR_WEBHOOK`: the discord webhook url for errors
 
 the following environment variables are optional: