diff --git a/.github/workflows/reusable-ci-astro.yml b/.github/workflows/reusable-ci-astro.yml
index 5edcdec..0281df2 100644
--- a/.github/workflows/reusable-ci-astro.yml
+++ b/.github/workflows/reusable-ci-astro.yml
@@ -15,8 +15,13 @@ on:
         type: string
         default: '24'
       pnpm-version:
+        description: >-
+          pnpm version for `pnpm/action-setup`. Empty, the default, makes the
+          action read `packageManager` from the caller's package.json, which
+          keeps CI on the version the repository actually pins. Set it only for
+          a repository that has no `packageManager` field.
         type: string
-        default: '10'
+        default: ''
       install-args:
         type: string
         default: '--frozen-lockfile'
diff --git a/.github/workflows/reusable-ci-node.yml b/.github/workflows/reusable-ci-node.yml
index 85f0c3e..c311c0f 100644
--- a/.github/workflows/reusable-ci-node.yml
+++ b/.github/workflows/reusable-ci-node.yml
@@ -24,9 +24,13 @@ on:
         type: string
         default: '24'
       pnpm-version:
-        description: 'pnpm version'
+        description: >-
+          pnpm version for `pnpm/action-setup`. Empty, the default, makes the
+          action read `packageManager` from the caller's package.json, which
+          keeps CI on the version the repository actually pins. Set it only for
+          a repository that has no `packageManager` field.
         type: string
-        default: '10'
+        default: ''
       package-manager:
         description: 'Package manager (pnpm, npm, yarn)'
         type: string