explain

var Long = heredoc.Doc(`
	Present documentation about various topics. You can list available topics,
	filter the list of available topics, render a single topic to the terminal,
	and automatically navigate to the webpage for a document. By default, it
	lists all available topics in a table with their topic, description category,
	and tags.
`)

this string is shown in the help output of this command.

var Short = "Present documentation about topics"

This string is shown in the help output of the root command.

var Use = "explain [topic] [--list]"

Cobra expects a string that explains the usage of a command and recommends the following syntax:

[ ] identifies an optional argument. Arguments that are not enclosed in brackets are required.
... indicates that you can specify multiple values for the previous argument.
|   indicates mutually exclusive information. You can use the argument to the left of the separator or the
    argument to the right of the separator. You cannot use both arguments in a single use of the command.
{ } delimits a set of mutually exclusive arguments when one of the arguments is required. If the arguments are
    optional, they are enclosed in brackets ([ ]).