diff --git a/.github/actions/sync-skills/action.yml b/.github/actions/sync-skills/action.yml
new file mode 100644
index 00000000..70985933
--- /dev/null
+++ b/.github/actions/sync-skills/action.yml
@@ -0,0 +1,107 @@
+name: "Mirror plugins to the skills repo"
+description: >-
+  Sync the built marketplace plugins into PostHog/skills on a branch, then
+  open an auto-merging PR.
+
+# Called by build-release.yml after the GitHub release is published.
+#
+# The target repo requires signed commits and changes via PR, so this mirrors
+# what PostHog/ai-plugin's own sync does: push a branch, have the GitHub API
+# create the commit on it (the API signs what it creates), open a PR, and let
+# auto-merge land it.
+#
+# The caller is responsible for checkout, Node/pnpm setup, `pnpm install`, and
+# `pnpm run build` — this action assumes dist/ already exists.
+
+inputs:
+  token:
+    description: "App token with write access to the target repo"
+    required: true
+  message:
+    description: "Commit message"
+    required: true
+
+outputs:
+  repo:
+    description: "The target repo, from push-manifest.json"
+    value: ${{ steps.sync.outputs.repo }}
+  branch:
+    description: "The sync branch that was pushed, empty when nothing changed"
+    value: ${{ steps.sync.outputs.branch }}
+  base:
+    description: "The branch the PR targets"
+    value: ${{ steps.sync.outputs.base }}
+
+runs:
+  using: composite
+  steps:
+    - id: sync
+      shell: bash
+      env:
+        TOKEN: ${{ inputs.token }}
+        MESSAGE: ${{ inputs.message }}
+      run: |
+        MANIFEST="dist/push-manifest.json"
+        TARGET_REPO=$(jq -r '.target_repo' "$MANIFEST")
+        # ghcommit-action resolves its `repository` input under $GITHUB_WORKSPACE.
+        WORK_DIR="$GITHUB_WORKSPACE/.skills-mirror"
+        rm -rf "$WORK_DIR"
+
+        echo "Cloning $TARGET_REPO..."
+        git clone --quiet "https://x-access-token:${TOKEN}@github.com/${TARGET_REPO}.git" "$WORK_DIR"
+
+        jq -c '.plugins[]' "$MANIFEST" | while read -r entry; do
+          NAME=$(echo "$entry" | jq -r '.name')
+          SOURCE="$PWD/dist/$(echo "$entry" | jq -r '.source')"
+          DEST="$WORK_DIR/$(echo "$entry" | jq -r '.destination')"
+          echo "  $NAME -> $(echo "$entry" | jq -r '.destination')"
+          if [ -d "$DEST" ]; then
+            find "$DEST" -mindepth 1 -not -name 'README.md' -exec rm -rf {} + 2>/dev/null || true
+          fi
+          mkdir -p "$DEST"
+          cp -r "$SOURCE"/. "$DEST"/
+        done
+
+        cd "$WORK_DIR"
+        git add -A
+        if git diff --cached --quiet; then
+          echo "Already up to date."
+          exit 0
+        fi
+
+        # The branch tip is the base commit, so this push creates no new
+        # (unsigned) commits; ghcommit-action lays the signed one on top.
+        BASE=$(git rev-parse --abbrev-ref HEAD)
+        BRANCH="chore/sync-plugins-$(date +%Y%m%d-%H%M%S)"
+        git push --quiet origin "HEAD:refs/heads/$BRANCH"
+        {
+          echo "repo=$TARGET_REPO"
+          echo "base=$BASE"
+          echo "branch=$BRANCH"
+        } >> "$GITHUB_OUTPUT"
+
+    - if: steps.sync.outputs.branch != ''
+      uses: planetscale/ghcommit-action@a6b150b81dca5dd027baa898604418eec9e11465 # v0.2.22
+      with:
+        commit_message: ${{ inputs.message }}
+        repo: ${{ steps.sync.outputs.repo }}
+        branch: ${{ steps.sync.outputs.branch }}
+        repository: .skills-mirror
+      env:
+        GITHUB_TOKEN: ${{ inputs.token }}
+
+    - if: steps.sync.outputs.branch != ''
+      shell: bash
+      env:
+        GH_TOKEN: ${{ inputs.token }}
+        TARGET_REPO: ${{ steps.sync.outputs.repo }}
+        BASE: ${{ steps.sync.outputs.base }}
+        BRANCH: ${{ steps.sync.outputs.branch }}
+        MESSAGE: ${{ inputs.message }}
+      run: |
+        PR_URL=$(gh pr create --repo "$TARGET_REPO" \
+          --base "$BASE" --head "$BRANCH" \
+          --title "$MESSAGE" \
+          --body "Automated plugin sync from context-mill.")
+        echo "Opened $PR_URL"
+        gh pr merge --repo "$TARGET_REPO" "$PR_URL" --auto --squash
diff --git a/.github/workflows/build-release.yml b/.github/workflows/build-release.yml
index 2df164c8..05ad4c07 100644
--- a/.github/workflows/build-release.yml
+++ b/.github/workflows/build-release.yml
@@ -266,64 +266,11 @@ jobs:
           private-key: ${{ secrets.SKILLS_PUSH_APP_PRIVATE_KEY }}
           repositories: skills,ai-plugin
 
-      - name: Push plugins to skills repo
-        id: skills_push
-        env:
-          SKILLS_REPO_TOKEN: ${{ steps.skills_token.outputs.token }}
-        run: |
-          MANIFEST="dist/push-manifest.json"
-          TARGET_REPO=$(jq -r '.target_repo' "$MANIFEST")
-          # ghcommit-action resolves its `repository` input under $GITHUB_WORKSPACE,
-          # so the clone lives there rather than in a mktemp dir.
-          WORK_DIR="$GITHUB_WORKSPACE/.skills-push"
-          rm -rf "$WORK_DIR"
-
-          echo "Cloning $TARGET_REPO..."
-          git clone "https://x-access-token:${SKILLS_REPO_TOKEN}@github.com/${TARGET_REPO}.git" "$WORK_DIR"
-          {
-            echo "target_repo=$TARGET_REPO"
-            echo "target_branch=$(git -C "$WORK_DIR" rev-parse --abbrev-ref HEAD)"
-          } >> "$GITHUB_OUTPUT"
-
-          # Read each plugin entry from the push manifest and sync to the destination
-          jq -c '.plugins[]' "$MANIFEST" | while read -r entry; do
-            NAME=$(echo "$entry" | jq -r '.name')
-            SOURCE="dist/$(echo "$entry" | jq -r '.source')"
-            DEST="$WORK_DIR/$(echo "$entry" | jq -r '.destination')"
-
-            echo "  Syncing $NAME → $(echo "$entry" | jq -r '.destination')"
-
-            # Clear destination (preserve README.md if present)
-            if [ -d "$DEST" ]; then
-              find "$DEST" -mindepth 1 -not -name 'README.md' -not -name '.' -exec rm -rf {} + 2>/dev/null || true
-            fi
-            mkdir -p "$DEST"
-
-            # Copy plugin contents
-            cp -r "$SOURCE"/. "$DEST"/
-          done
-
-          cd "$WORK_DIR"
-          git add -A
-          if git diff --cached --quiet; then
-            echo "No changes to push"
-            echo "changed=false" >> "$GITHUB_OUTPUT"
-          else
-            echo "changed=true" >> "$GITHUB_OUTPUT"
-          fi
-
-      # Both target repos require signed commits, so the mirrored content is
-      # committed through the GitHub API instead of pushed with git.
-      - name: Commit plugins to skills repo
-        if: steps.skills_push.outputs.changed == 'true'
-        uses: planetscale/ghcommit-action@a6b150b81dca5dd027baa898604418eec9e11465 # v0.2.22
+      - name: Mirror plugins to the skills repo
+        uses: ./.github/actions/sync-skills
         with:
-          commit_message: Update generated plugins from context-mill ${{ env.RELEASE_TAG }}
-          repo: ${{ steps.skills_push.outputs.target_repo }}
-          branch: ${{ steps.skills_push.outputs.target_branch }}
-          repository: .skills-push
-        env:
-          GITHUB_TOKEN: ${{ steps.skills_token.outputs.token }}
+          token: ${{ steps.skills_token.outputs.token }}
+          message: Update generated plugins from context-mill ${{ env.RELEASE_TAG }}
 
       - name: Push omnibus skills to ai-plugin repo
         id: ai_plugin_push
@@ -375,7 +322,7 @@ jobs:
       # workspace rather than a mktemp dir, so drop them before any later step runs.
       - name: Remove the mirror clones
         if: always()
-        run: rm -rf "$GITHUB_WORKSPACE/.skills-push" "$GITHUB_WORKSPACE/.ai-plugin-push"
+        run: rm -rf "$GITHUB_WORKSPACE/.skills-mirror" "$GITHUB_WORKSPACE/.ai-plugin-push"
 
       # Mirror the release to S3 so consumers have a second origin to fetch from
       # when GitHub Releases is unavailable.
diff --git a/scripts/lib/marketplace-generator.js b/scripts/lib/marketplace-generator.js
index 74ca1ec6..b22a3e34 100644
--- a/scripts/lib/marketplace-generator.js
+++ b/scripts/lib/marketplace-generator.js
@@ -96,8 +96,13 @@ function writeSkillReminderHook(pluginDir) {
                 {
                     hooks: [
                         {
+                            // Invoked through bash so the hook survives losing
+                            // its executable bit: the plugin trees reach
+                            // PostHog/skills as GitHub-API-signed commits
+                            // (createCommitOnBranch), and that API has no file
+                            // mode support — everything lands as 100644.
                             type: 'command',
-                            command: '${CLAUDE_PLUGIN_ROOT}/hooks/skill-reminder.sh',
+                            command: 'bash ${CLAUDE_PLUGIN_ROOT}/hooks/skill-reminder.sh',
                         },
                     ],
                 },