Move flutter-bundled dart comment

script/tool/README.md

diff --git a/script/tool/README.md b/script/tool/README.md
index a638602..9b91b03 100644
--- a/script/tool/README.md
+++ b/script/tool/README.md
@@ -15,6 +15,8 @@
 a general-purpose tool, but updates are still published for use in
 flutter/packages.)
 
+The commands in tools require the Flutter-bundled version of Dart to be the first `dart` loaded in the path.
+
 ### From Source (flutter/plugins only)
 
 Set up:
@@ -51,8 +53,6 @@
 All examples assume running from source; see above for running the
 published version instead.
 
-Some commands require the Flutter-bundled version of Dart to be the first `dart` loaded into path (or the only version of Dart installed).
-
 Most commands take a `--packages` argument to control which package(s) the
 command is targetting. An package name can be any of:
 - The name of a package (e.g., `path_provider_android`).