diff --git a/.gitea/workflows/ci.yaml b/.gitea/workflows/ci.yaml
index 40ec896..3db0222 100644
--- a/.gitea/workflows/ci.yaml
+++ b/.gitea/workflows/ci.yaml
@@ -23,6 +23,8 @@ jobs:
     name: Codex
     runs-on: ubuntu
     needs: release-tag-version
+    env:
+      CODEX_OAUTH: ${{ secrets.CODEX_OAUTH }}
     steps:
     - name: 測試工具
       id: codex
diff --git a/action.yml b/action.yml
index 2886409..80abb0a 100644
--- a/action.yml
+++ b/action.yml
@@ -14,14 +14,17 @@ runs:
   using: 'composite'
   steps:
   - name: 安裝工具
-    env:
-      OAUTH: ${{ secrets.CODEX_OAUTH }}
     run: |
+      if [ -z "$CODEX_OAUTH" ]; then
+        echo 'CODEX_OAUTH environment variable is required (set it from secrets.CODEX_OAUTH in the caller workflow).' >&2
+        exit 1
+      fi
+
       npm install -g @openai/codex
 
       oauth_file="$HOME/.codex/auth.json"
       install -d -m 700 "$(dirname "$oauth_file")"
-      printf '%s' "$OAUTH" | base64 -d > "$oauth_file"
+      printf '%s' "$CODEX_OAUTH" | base64 -d > "$oauth_file"
       chmod 600 "$oauth_file"
     shell: bash
   - name: 執行工具