diff --git a/.github/workflows/manually_build_for_testing.yml b/.github/workflows/manually_build_for_testing.yml
index b1dc17f3..e5580ee4 100644
--- a/.github/workflows/manually_build_for_testing.yml
+++ b/.github/workflows/manually_build_for_testing.yml
@@ -4,9 +4,8 @@ on:
   workflow_dispatch:
     inputs:
       sha:
-        description: 'commit id'
+        description: 'commit id (SHA-1 hash)'
         required: true
-        default: 'latest'
         type: string
       artifact:
         description: 'select which job to run("all" will make all jobs run)'