I use the -h argument allot:
$ pihole -h
Usage: pihole [options]
Example: 'pihole -w -h'
Add '-h' after specific commands for more information on usage
Whitelist/Blacklist Options:
-w, whitelist Whitelist domain(s)
-b, blacklist Blacklist domain(s)
--regex, regex Regex blacklist domains(s)
--white-regex Regex whitelist domains(s)
--wild, wildcard Wildcard blacklist domain(s)
--white-wild Wildcard whitelist domain(s)
Add '-h' for more info on whitelist/blacklist usage
Debugging Options:
-d, debug Start a debugging session
Add '-c' or '--check-database' to include a Pi-hole database integrity check
Add '-a' to automatically upload the log to tricorder.pi-hole.net
-f, flush Flush the Pi-hole log
-r, reconfigure Reconfigure or Repair Pi-hole subsystems
-t, tail [arg] View the live output of the Pi-hole log.
Add an optional argument to filter the log
(regular expressions are supported)
Options:
-a, admin Web interface options
Add '-h' for more info on Web Interface usage
-c, chronometer Calculates stats and displays to an LCD
Add '-h' for more info on chronometer usage
-g, updateGravity Update the list of ad-serving domains
-h, --help, help Show this help dialog
-l, logging Specify whether the Pi-hole log should be used
Add '-h' for more info on logging usage
-q, query Query the adlists for a specified domain
Add '-h' for more info on query usage
-up, updatePihole Update Pi-hole subsystems
Add '--check-only' to exit script before update is performed.
-v, version Show installed versions of Pi-hole, Web Interface & FTL
Add '-h' for more info on version usage
uninstall Uninstall Pi-hole from your system
status Display the running status of Pi-hole subsystems
enable Enable Pi-hole subsystems
disable Disable Pi-hole subsystems
Add '-h' for more info on disable usage
restartdns Full restart Pi-hole subsystems
Add 'reload' to update the lists and flush the cache without restarting the DNS server
Add 'reload-lists' to only update the lists WITHOUT flushing the cache or restarting the DNS server
checkout Switch Pi-hole subsystems to a different GitHub branch
Add '-h' for more info on checkout usage
arpflush Flush information stored in Pi-hole's network tables
$ pihole -w -h
Usage: pihole -w [options] <domain> <domain2 ...>
Example: 'pihole -w site.com', or 'pihole -w site1.com site2.com'
Whitelist one or more domains
Options:
-d, --delmode Remove domain(s) from the whitelist
-nr, --noreload Update whitelist without reloading the DNS server
-q, --quiet Make output less verbose
-h, --help Show this help dialog
-l, --list Display all your whitelistlisted domains
--nuke Removes all entries in a list
--comment "text" Add a comment to the domain. If adding multiple domains the same comment will be used for all
EDIT: Oh and you also have Bash completion (double TAB):
$ pihole
admin disable reconfigure updateGravity
arpflush enable regex updatePihole
blacklist flush restartdns version
checkout help status whitelist
chronometer logging tail wildcard
debug query uninstall
$ pihole whitelist --
--delmode --list --noreload --nuke --quiet
EDIT2: Almost forgot but there is also a man page:
$ man pihole
[..]
DESCRIPTION
Available commands and options:
-w, whitelist [options] [<domain1> <domain2 ...>]
Adds or removes specified domain or domains to the
Whitelist
[..]
English though 