diff --git a/action.yml b/action.yml
index 41872296..8cfb16ff 100644
--- a/action.yml
+++ b/action.yml
@@ -4,10 +4,11 @@ author: 'peaceiris'
 inputs:
   github_token:
     description: 'Auth token used to manage issues or pull requests'
-    default: ${{ github.token }}
+    required: true
   config_file:
     description: 'Path to action setting file'
     default: '.github/commenter.yml'
+    required: false
 runs:
   using: 'node12'
   main: 'lib/index.js'