diff --git a/README.md b/README.md
index 76acc86..090e91e 100644
--- a/README.md
+++ b/README.md
@@ -51,6 +51,18 @@ The behavior of existing apps using "su" will NOT change. You can ask the develo
 
 For existing apps that already support Shizuku, add support for Sui (including changes for Shizuku API v11) should only take less than half an hour.
 
+### Command-line tool
+
+Sui has a command-line tool to allow you to run commands. It's not a full shell (for now).
+
+Since Sui does not add files to `PATH`, the files need to be copied manually. See `/data/adb/sui/post-install.example.sh` to learn how to do this automatically.
+
+After the files are correctly copied, use `sui --help` to see how to use the tool.
+
+> What's the meaning of this tool? There is already "su" from Magisk.
+> 
+> This does helped me to investigate [a bug of Magisk](https://github.com/topjohnwu/Magisk/issues/3976) that happens rarely. At that time, Magisk's su is not available. 
+
 ## Guide for application developers
 
 https://github.com/RikkaApps/Shizuku-API
\ No newline at end of file
diff --git a/template/magisk_module/README.md b/template/magisk_module/README.md
index 6084e98..3212664 100644
--- a/template/magisk_module/README.md
+++ b/template/magisk_module/README.md
@@ -6,10 +6,14 @@
 
 ### v11.5.0 (2021-03-02)
 
-- (Experimental) Provide a simple tool which can run commands, this tool can be used in terminal apps and adb shell
+- Provide a experimental tool which can run commands, this tool can be used in terminal apps and adb shell (see README for more)
 - Filter out packages without components
 - Filter out nonexistent packages added by `MATCH_UNINSTALLED_PACKAGES` flag
 
+> What's the meaning of the command-line tool? There is already "su" from Magisk.
+> 
+> This does helped me to investigate [a bug of Magisk](https://github.com/topjohnwu/Magisk/issues/3976) that happens rarely. At that time, Magisk's su is not available. 
+
 ### v11.4.5 (2021-02-21)
 
 - Fix random authorization dialog or management ui not showing
diff --git a/template/magisk_module/post-install.example.sh b/template/magisk_module/post-install.example.sh
index 389ca84..1cbe0ef 100644
--- a/template/magisk_module/post-install.example.sh
+++ b/template/magisk_module/post-install.example.sh
@@ -6,8 +6,8 @@
 # Rename this file to /data/adb/sui/post-install.sh to allow this script to be loaded.
 
 # Variables:
-# SUI_DEX:  the path to the dex of the command-line tool
-# SUI_WRAPPER:      the path to the wrapper script to start the dex
+# SUI_DEX:      the path to the dex of the command-line tool
+# SUI_WRAPPER:  the path to the wrapper script to start the dex
 
 copy_cmd_tool() {
   APP_APPLICATION_ID=$1