It depends on what version of ftp server they are using, on most you can do something like:
> ? [command]
and that will give you the help for that command. This server looks like it's still a work in progress most of the commands are raw commands other ones are unidentified and still in development.
USER = user name for login
PASS = password for login
ACCT* = change accounts when already logged in
CWD = change working directory
XCWD = change working directory locally
CDUP = change directoy up
XCUP = change directory up locally
QUIT = quit session
REIN* = reinitializes the connection
PORT = specify ftp data port
PASV = use high ports for ftp data if you have a firewall
TYPE = set file transfer type
STRU = set file structure for transfer: File, Record, Page.
MODE = set file transfer mode
RETR = retrieve a remote file (get)
STOR = store a remote file on the host (put)
STOU = store a file uniquely
APPE = append to a remote file
ALLO* = allocates space to recieve a file
REST = restores an interrupted file transfer
RNFR = rename file from
RNTO = rename file to
ABOR = abort transfer currently in progress
DELE = delete a file
MDTM = last modified time of a file
RMD = remove directory
XRMD = local remove directory
MKD = make directory
XMKD = local make directory
PWD = print working directory
XPWD = print local working directory
SIZE = gives you the file size
LIST = lists files in a directory
NLST = returns a file list when you specify the directory
SITE = exectutes a site specific command
SYST = returns the system type
STAT = general status of server
HELP = returns help
NOOP = does nothing except return a response
FEAT OPTS SMNT* ADAT* AUTH* CCC* CONF* ENC* MIC* PBSZ* and PROT* must be version specific features.
http://www.uoguelph.ca/~fli/ftpCommands.htm