diff --git a/engine/scripts/rbe.gclient b/engine/scripts/rbe.gclient
index 603a408d0d..98022cc484 100644
--- a/engine/scripts/rbe.gclient
+++ b/engine/scripts/rbe.gclient
@@ -2,13 +2,20 @@
 # or just run gclient sync in an empty directory with this file.
 solutions = [
   {
-    "custom_vars": {
-      "use_rbe": True,
-    },
     "deps_file": "DEPS",
     "managed": False,
     "name": ".",
     "safesync_url": "",
+
+    # If you are using SSH to connect to GitHub, change the URL to:
+    # git@github.com:flutter/flutter.git
     "url": "https://github.com/flutter/flutter.git",
+
+    "custom_vars": {
+      "use_rbe": True,
+
+      # Uncomment download_emsdk below if you plan to build the web engine.
+      # "download_emsdk": True,
+    },
   },
 ]
\ No newline at end of file
diff --git a/engine/scripts/standard.gclient b/engine/scripts/standard.gclient
index 7dbba841e0..a05a39e336 100644
--- a/engine/scripts/standard.gclient
+++ b/engine/scripts/standard.gclient
@@ -7,6 +7,14 @@ solutions = [
     "managed": False,
     "name": ".",
     "safesync_url": "",
+
+    # If you are using SSH to connect to GitHub, change the URL to:
+    # git@github.com:flutter/flutter.git
     "url": "https://github.com/flutter/flutter.git",
+
+    # Uncomment the custom_vars section below if you plan to build the web engine.
+    # "custom_vars": {
+    #   "download_emsdk": True,
+    # },
   },
 ]
\ No newline at end of file