diff --git a/docs/copy_directory.md b/docs/copy_directory.md
index 3722a9b..0cb54bc 100644
--- a/docs/copy_directory.md
+++ b/docs/copy_directory.md
@@ -2,8 +2,7 @@
A rule that copies a directory to another place.
-The rule uses a Bash command on Linux/macOS/non-Windows, and a cmd.exe command
-on Windows (no Bash is required).
+The rule uses a precompiled binary to perform the copy, so no shell is required.
@@ -15,7 +14,7 @@ copy_directory(name,