Here is a list of commands:

help

Displays this wall of text.

+[amount] [unit]

Adds to the working time

-[amount] [unit]

Subtracts from the working time

diff [month] [day] [year] diff [month] [day] [year] [hh:mm:ss] diff [month] [day] [year] [hh:mm:ss] [am|pm]

Gets difference to another date

set [month] [day] [year] set [month] [day] [year] [hh:mm:ss] set [month] [day] [year] [hh:mm:ss] [am|pm]

Sets working time to another time

setorg

Sets original time to working time

clear

Clears the screen and resets to original time

now

Sets working time to current time

show

Show working time