fix: improve command line argument description

Author: yumetodo

README.md

@@ -71,6 +71,18 @@ export QIITA_ACCESS_TOKEN=9226168a5ef65f8e81153b460e7c78f8b8e53394
 npx qiita_export_all
 ```
 
+### Command Line options
+
+```plain
+Usage: qiita_export_all [options]
+
+Options:
+  -V, --version        output the version number
+  -u, --user-id <id>   Qiita user id you want to download(default: the user who get QIITA_ACCESS_TOKEN).
+  -o, --output <path>  Write output to <path> instead of current directory.
+  -h, --help           output usage information
+```
+
 ## Note
 
 - md ファイルは UTF-8 でエクスポートします

bin/index.js

@@ -67,8 +67,9 @@ if (token == null) {
 } else {
   program
     .version("1.4.0")
-    .option("-u, --user-id <id>", "user id")
-    .option("-o, --output <file>", "Write output to <file> instead of current directory.")
+    .name("qiita_export_all")
+    .option("-u, --user-id <id>", "Qiita user id you want to download(default: the user who get QIITA_ACCESS_TOKEN).")
+    .option("-o, --output <path>", "Write output to <path> instead of current directory.")
     .parse(process.argv);
   main(program.userId, program.output).catch(er => {
     console.error(er.stack, er);