diff --git a/.github/workflows/c-tests.yml b/.github/workflows/c-tests.yml
index b3efdb288b..0e87488fdb 100644
--- a/.github/workflows/c-tests.yml
+++ b/.github/workflows/c-tests.yml
@@ -3,11 +3,11 @@ name: C/CCpp tests
 on:
   workflow_call:
     inputs:
-      compiler-ref:
-        required: `network-structure`
+      compiler-ref: `network-structure`
+        required: true
         type: string
-      runtime-ref:
-        required: `network-structure`
+      runtime-ref: `network-structure`
+        required: true
         type: string
       use-cpp:
         required: false