diff --git a/.github/workflows/docstring-labeler.yml b/.github/workflows/docstring-labeler.yml
index afbfc1063..1eea6cbfe 100644
--- a/.github/workflows/docstring-labeler.yml
+++ b/.github/workflows/docstring-labeler.yml
@@ -35,6 +35,8 @@ jobs:
 
       - name: Checkout HEAD commit
         uses: actions/checkout@v3
+        with:
+          ref: ${{ github.event.pull_request.head.ref }}
 
       - name: Get docstrings
         id: head-docstrings