task add [tags] [attrs] desc...
       task list [tags] [attrs] desc...
       task long [tags] [attrs] desc...
       task ls [tags] [attrs] desc...
       task completed [tags] [attrs] desc...
       task ID [tags] [attrs] [desc...]
       task ID /from/to/
       task delete ID
       task undelete ID
       task info ID
       task start ID
       task done ID
       task projects
       task tags
       task summary
       task history
       task ghistory
       task next
       task calendar
       task active
       task overdue
       task oldest
       task newest
       task stats
       task usage
       task export
       task color
       task version

ID is the numeric identifier displayed by the 'task list' command

Tags are arbitrary words, any quantity:
  +tag               The + means add the tag
  -tag               The - means remove the tag

Attributes are:
  project:           Project name
  priority:          Priority
  due:               Due date
  fg:                Foreground color
  bg:                Background color

Any command or attribute name may be abbreviated if still unique:
  task list project:Home
  task li       pro:Home

Some task descriptions need to be escaped because of the shell:
  task add "quoted ' quote"
  task add escaped \' quote

Many characters have special meaning to the shell, including:
  $ ! ' " ( ) ; \ ` * ? { } [ ] < > | & % # ~