# Name, usage and synopsis of the tool.
	# It is mainly used in `usage`.
	# Should be correctly set by the client before calling `usage`
	# A multi-line string is recommended.
	#
	# eg. `"Usage: tool [OPTION]... [FILE]...\nDo some things."`
	var tool_description: String = "Usage: [OPTION]... [ARG]..." is writable