diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8cc26d2995e73..4755210719612 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -106,6 +106,9 @@ jobs:
       - name: install clang
         run: src/ci/scripts/install-clang.sh
         if: success() && !env.SKIP_JOB
+      - name: install tidy
+        run: src/ci/scripts/install-tidy.sh
+        if: success() && !env.SKIP_JOB
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
         if: success() && !env.SKIP_JOB
@@ -483,6 +486,9 @@ jobs:
       - name: install clang
         run: src/ci/scripts/install-clang.sh
         if: success() && !env.SKIP_JOB
+      - name: install tidy
+        run: src/ci/scripts/install-tidy.sh
+        if: success() && !env.SKIP_JOB
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
         if: success() && !env.SKIP_JOB
@@ -607,6 +613,9 @@ jobs:
       - name: install clang
         run: src/ci/scripts/install-clang.sh
         if: success() && !env.SKIP_JOB
+      - name: install tidy
+        run: src/ci/scripts/install-tidy.sh
+        if: success() && !env.SKIP_JOB
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
         if: success() && !env.SKIP_JOB
diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index b415eb5961bb3..6518a88732f66 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -173,6 +173,10 @@ x--expand-yaml-anchors--remove:
         run: src/ci/scripts/install-clang.sh
         <<: *step
 
+      - name: install tidy
+        run: src/ci/scripts/install-tidy.sh
+        <<: *step
+
       - name: install WIX
         run: src/ci/scripts/install-wix.sh
         <<: *step
diff --git a/src/ci/scripts/install-tidy.sh b/src/ci/scripts/install-tidy.sh
new file mode 100755
index 0000000000000..fab126453fdc9
--- /dev/null
+++ b/src/ci/scripts/install-tidy.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+# This script downloads and installs the tidy binary from Homebrew.
+
+set -euo pipefail
+IFS=$'\n\t'
+
+source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
+
+# Only the macOS arm64/aarch64 GitHub Actions runner needs to have tidy
+# installed; other platforms have it preinstalled.
+
+if isMacOS; then
+    platform=$(uname -m)
+    case $platform in
+        x86_64)
+            ;;
+        arm64)
+            brew install tidy-html5
+            ;;
+        *)
+            echo "unsupported architecture: ${platform}"
+            exit 1
+    esac
+fi