diff --git a/README.md b/README.md
index 3b028ba..7553dd1 100644
--- a/README.md
+++ b/README.md
@@ -50,7 +50,7 @@ Getting started
 In order to compile a Nirum package (`examples/`) to a Python package:
 
     $ mkdir out/  # directory to place generated Python files
-    $ nirum -o out/ examples/
+    $ nirum -t python -o out/ examples/
 
 For more infomration, use `--help` option:
 
@@ -64,7 +64,7 @@ For more infomration, use `--help` option:
       -h,--help                Show this help text
       -v,--version             Show version
       -o,--output-dir DIR      Output directory
-      -t,--target TARGET       Target language name
+      -t,--target TARGET       Target language name. Available: docs, python
       DIR                      Package directory
 
 Building
diff --git a/nirum.cabal b/nirum.cabal
index d835b21..6946b8c 100644
--- a/nirum.cabal
+++ b/nirum.cabal
@@ -56,7 +56,6 @@ library
                ,       bytestring
                ,       cmark                    >=0.5     && <0.6
                ,       containers               >=0.5.6.2 && <0.6
-               ,       cmdargs                  >=0.10.14 && <0.11
                ,       directory                >=1.2.5   && <1.4
                ,       email-validate           >=2.0.0   && <3.0.0
                ,       filepath                 >=1.4     && <1.5
diff --git a/src/Nirum/Cli.hs b/src/Nirum/Cli.hs
index 4f27b45..de0dbaf 100644
--- a/src/Nirum/Cli.hs
+++ b/src/Nirum/Cli.hs
@@ -183,6 +183,7 @@ main = do
              OPT.help "Output directory") <*>
         OPT.strOption
             (OPT.long "target" <> OPT.short 't' <> OPT.metavar "TARGET" <>
-             OPT.help "Target language name") <*>
+             OPT.help [qq|Target language name.
+                          Available: $targetNamesText|]) <*>
         OPT.strArgument
             (OPT.metavar "DIR" <> OPT.help "Package directory")