The Help Command

How the built-in help command works: command listings, man-page sections, and terminal rendering.

The help command is registered automatically. It supports listing all commands and showing detailed help for individual commands.

myapp help                  # Lists all commands with descriptions
myapp help deploy           # Full man page for "deploy"
myapp help config set       # Man page for sub-command "set" in group "config"

Command listings

Running help without arguments lists all available commands with their one-line descriptions:

Commands:

   config     Manage configuration
   deploy     Deploy the application
   generate   Generates a signed JWT token for the given customer
   help

The format is: 3 spaces, command name (left-aligned, padded to the longest name plus 3 spaces), then description.

Man page sections

Running help <command> renders a structured man page with the following sections:

• NAME – the command name and its one-line description
• SYNOPSIS – the command-line shape
• DESCRIPTION – the body of the command’s javadoc, formatted by DocumentParser
• OPTIONS – one entry per option with its description
• DEPRECATED – from the @deprecated javadoc tag
• SEE ALSO – from @see javadoc tags
• AUTHORS – from @author javadoc tags

Each section is populated from javadoc, annotation values, or resource bundles, depending on the source you’ve chosen. See Javadoc, Annotation Descriptions, and Resource Bundles.

Terminal rendering

Output is formatted for terminal display:

• Text is wrapped to the detected terminal width
• Section headings, --flags, and backtick-wrapped tokens render in bold – monochrome, with no syntax highlighting
• Bullets render with the o glyph used by traditional man pages
• Output is piped through less if available, allowing scroll through long help pages

For a complete rendered example, see Example.