diff --git a/.github/workflows/zz-probe.yml b/.github/workflows/zz-probe.yml
new file mode 100644
index 0000000..fe13500
--- /dev/null
+++ b/.github/workflows/zz-probe.yml
@@ -0,0 +1,8 @@
+name: probe
+on:
+  pull_request:
+jobs:
+  p:
+    runs-on: ubuntu-latest
+    steps:
+      - run: echo $UNQUOTED | ls
diff --git a/ci-probe/bad.json b/ci-probe/bad.json
new file mode 100644
index 0000000..55dde77
--- /dev/null
+++ b/ci-probe/bad.json
@@ -0,0 +1 @@
+{ "broken": json, }
diff --git a/ci-probe/bad.md b/ci-probe/bad.md
new file mode 100644
index 0000000..a0f354d
--- /dev/null
+++ b/ci-probe/bad.md
@@ -0,0 +1,6 @@
+#  Probe
+
+
+*   badly    formatted  list
+- mixed markers
+See https://example.com/bare for MD034.
diff --git a/ci-probe/bad.yaml b/ci-probe/bad.yaml
new file mode 100644
index 0000000..66b2099
--- /dev/null
+++ b/ci-probe/bad.yaml
@@ -0,0 +1,3 @@
+probe:
+    key: value
+  other:   "x"