diff --git a/src/cmd/go/alldocs.go b/src/cmd/go/alldocs.go
index d884f7d5f384f8..0645780966b283 100644
--- a/src/cmd/go/alldocs.go
+++ b/src/cmd/go/alldocs.go
@@ -495,15 +495,6 @@
 // (gofmt), a fully qualified path (/usr/you/bin/mytool), or a
 // command alias, described below.
 //
-// To convey to humans and machine tools that code is generated,
-// generated source should have a line that matches the following
-// regular expression (in Go syntax):
-//
-// 	^// Code generated .* DO NOT EDIT\.$
-//
-// The line may appear anywhere in the file, but is typically
-// placed near the beginning so it is easy to find.
-//
 // Note that go generate does not parse the file, so lines that look
 // like directives in comments or multiline strings will be treated
 // as directives.
@@ -515,6 +506,15 @@
 // Quoted strings use Go syntax and are evaluated before execution; a
 // quoted string appears as a single argument to the generator.
 //
+// To convey to humans and machine tools that code is generated,
+// generated source should have a line that matches the following
+// regular expression (in Go syntax):
+//
+// 	^// Code generated .* DO NOT EDIT\.$
+//
+// This line must appear before the first non-comment, non-blank
+// text in the file.
+//
 // Go generate sets several variables when it runs the generator:
 //
 // 	$GOARCH
diff --git a/src/cmd/go/internal/generate/generate.go b/src/cmd/go/internal/generate/generate.go
index c7401948b8b314..b1e001c8008ba5 100644
--- a/src/cmd/go/internal/generate/generate.go
+++ b/src/cmd/go/internal/generate/generate.go
@@ -52,15 +52,6 @@ that can be run locally. It must either be in the shell path
 (gofmt), a fully qualified path (/usr/you/bin/mytool), or a
 command alias, described below.
 
-To convey to humans and machine tools that code is generated,
-generated source should have a line that matches the following
-regular expression (in Go syntax):
-
-	^// Code generated .* DO NOT EDIT\.$
-
-The line may appear anywhere in the file, but is typically
-placed near the beginning so it is easy to find.
-
 Note that go generate does not parse the file, so lines that look
 like directives in comments or multiline strings will be treated
 as directives.
@@ -72,6 +63,15 @@ arguments when it is run.
 Quoted strings use Go syntax and are evaluated before execution; a
 quoted string appears as a single argument to the generator.
 
+To convey to humans and machine tools that code is generated,
+generated source should have a line that matches the following
+regular expression (in Go syntax):
+
+	^// Code generated .* DO NOT EDIT\.$
+
+This line must appear before the first non-comment, non-blank
+text in the file.
+
 Go generate sets several variables when it runs the generator:
 
 	$GOARCH