Minecraft Op Commands

Source: Minecraft Server/OP Commands. Minecraft Server Host.net

Command Description
ban <playername> [reason]Blacklists the name playername from the server so that they can no longer connect. Note: Bans supersede any whitelisting in place.
ban-ip <ip-address>Blacklists an IP address so that all subsequent connections from it are rejected.
banlist [ips]Displays the banlist. To display banned IP addresses, use the command banlist ips
deop <playername>Revokes a player's operator status.
difficulty <0-3>Changes the difficulty. 0 is peaceful, 1 is easy, 2 is normal, and 3 is hard. Only works in 12w32a or later.
gamemode <0/1/2> [playername]Changes the game mode for playername to Survival (0) mode, Creative (1) mode or Adventure (2) mode. If no playername is given, it will set your own gamemode. Remember, this will only affect playername and no one else. Note: Player must currently be online for the command to work.
defaultgamemode <0/1/2>Sets the default game mode that is shown on the world selection menu. New players that join the world will be put into the default game mode; i.e., if the default game mode is creative, new players will start in creative. This command was added in snapshot 12w22a. This command also appears in the single player cheats, but seems useful in multiplayer only.
give <playername> <data-value> [amount] [damage-value]Spawns amount (defaults to 1) of the item defined by data-value with the specified damage value (defaults to 0) at playername 's location. For example typing /give John 4 30 will give a player called John 30 blocks of normal cobblestone non-smelted.
help or ?Shows a list of available server commands. Note: banlist, whitelist, toggledownfall, xp, tell, me, and kill commands are not listed.
kick <playername> [reason]Forcibly disconnects playername from the server.
listShows the names of all currently-connected players (the same can be achieved when pressing tab)
op <playername>Grants playername operator status on the server.
pardon <playername>Removes playername from the blacklist, allowing them to connect again.
pardon-ip <ip-address>Removes ip-address from the IP blacklist, allowing players from that IP address to connect to the server.
save-allForces the server to write all pending changes to the world to disk.
save-offDisables the server writing to the world files. All changes will temporarily be queued.
save-onEnables the server writing to the world files. This is the default behavior.
say <message>Broadcasts message to all players on the server (in bright pink letters)
spawnpoint" <player> [x] [y] [z]Sets the spawnpoint of that player to that position, or to the current position if x y and z are not specified. Only works in 12w32a and later.
stopGracefully shuts down the server.
time <set/add> <number>Set or increment (add to) the world time. number is an integer between 0 and 24000, inclusive, where 0 is dawn, 6000 midday, 12000 dusk and 18000 midnight (i.e. the clock is bisected; left side is night, right side is day). Note: You can also subtract from the current time by using the 'add X' modifier, by using a negative value (i.e. 'time add -6000' would change midnight to dusk).
toggledownfallToggles rain and snow.
tp <targetplayer>Teleports yourself to targetplayer 's location
tp <playername> <targetplayer>Teleports player playername to targetplayer 's location
tp <playername> <x> <y> <z>Teleports player playername to coordinates x,y,z. (the y value cannot be smaller than 0).
weather <clear/rain/thunder> <seconds>Changes the weather. Only works in 12w32a or later.
whitelist <add/remove> <playername>Adds or removes playername from the whitelist.
whitelist <list>Displays all players in the whitelist.
whitelist <on/off>Enables/disables the server's use of a whitelist. Note: Server ops will always be able to connect when the whitelist is active, even if their names do not appear in the whitelist.
whitelist reloadReloads the list of playernames in white-list.txt from disk (used when white-list.txt has been modified outside of Minecraft).
xp <amount> <playername>Gives the specified user the given number of orbs. Maximum is 5000 per command. Negative amounts may be used to remove experience progress, but not actual levels.