diff --git a/.github/workflows/check-certificates.yml b/.github/workflows/check-certificates.yml
index b0d404f6..2d834997 100644
--- a/.github/workflows/check-certificates.yml
+++ b/.github/workflows/check-certificates.yml
@@ -9,13 +9,13 @@ on:
     paths:
       - ".github/workflows/check-certificates.ya?ml"
   schedule:
-    # run every 10 hours
+    # Run every 10 hours.
     - cron: "0 */10 * * *"
   workflow_dispatch:
   repository_dispatch:
 
 env:
-  # Begin notifications when there are less than this many days remaining before expiration
+  # Begin notifications when there are less than this many days remaining before expiration.
   EXPIRATION_WARNING_PERIOD: 30
 
 jobs:
@@ -32,9 +32,10 @@ jobs:
 
       matrix:
         certificate:
-          - identifier: macOS signing certificate # Text used to identify the certificate in notifications
-            certificate-secret: APPLE_SIGNING_CERTIFICATE_P12  # The name of the secret that contains the certificate
-            password-secret: KEYCHAIN_PASSWORD  # The name of the secret that contains the certificate password
+          # Additional certificate definitions can be added to this list.
+          - identifier: macOS signing certificate # Text used to identify certificate in notifications.
+            certificate-secret: APPLE_SIGNING_CERTIFICATE_P12 # Name of the secret that contains the certificate.
+            password-secret: KEYCHAIN_PASSWORD # Name of the secret that contains the certificate password.
           - identifier: Windows signing certificate
             certificate-secret: WINDOWS_SIGNING_CERTIFICATE_PFX
             password-secret: WINDOWS_SIGNING_CERTIFICATE_PASSWORD
@@ -42,7 +43,7 @@ jobs:
     steps:
       - name: Set certificate path environment variable
         run: |
-          # See: https://docs.github.com/en/free-pro-team@latest/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable
+          # See: https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-environment-variable
           echo "CERTIFICATE_PATH=${{ runner.temp }}/certificate.p12" >> "$GITHUB_ENV"
 
       - name: Decode certificate
@@ -64,7 +65,6 @@ jobs:
             exit 1
           )
 
-      # See: https://github.com/rtCamp/action-slack-notify
       - name: Slack notification of certificate verification failure
         if: failure()
         uses: rtCamp/action-slack-notify@v2.1.0
@@ -104,7 +104,7 @@ jobs:
 
           DAYS_BEFORE_EXPIRATION="$((($(date --utc --date="$EXPIRATION_DATE" +%s) - $(date --utc +%s)) / 60 / 60 / 24))"
 
-          # Display the expiration information in the log
+          # Display the expiration information in the log.
           echo "Certificate expiration date: $EXPIRATION_DATE"
           echo "Days remaining before expiration: $DAYS_BEFORE_EXPIRATION"
 
@@ -119,7 +119,7 @@ jobs:
           fi
 
       - name: Slack notification of pending certificate expiration
-        # Don't send spurious expiration notification if verification fails
+        # Don't send spurious expiration notification if verification fails.
         if: failure() && steps.check-expiration.outcome == 'failure'
         uses: rtCamp/action-slack-notify@v2.1.0
         env: