diff --git a/.github/workflows/build_directories.yaml b/.github/workflows/build_directories.yaml
index 8b7a5ed..95128fa 100644
--- a/.github/workflows/build_directories.yaml
+++ b/.github/workflows/build_directories.yaml
@@ -2,6 +2,8 @@ name: Build directory markdown files
 
 on:
   push:
+    branches:
+      - master
   workflow_dispatch:
 
 jobs: