Here's a full list of the TShock commands available after you install TShock (can be done via your Mod Manager in the control-panel):

All these can either be issued from in-game when you've authorized your account as SuperAdmin, or via the control-panel web console. If you use the web console, you should not put a "/"-sign before the command.

/helpDisplay all available commands
/authAuthorizes your user as SuperAdmin, must have the auth code.
/userUser functions
/login Logs in to an account
/logoutLogs out of an account
/passwordChange your account password
/registerRegister a new account
/accountinfoReveals information regarding a specific account
/banBans a player.
/broadcast (/bc, /say)Broadcast a server-wide message
/displaylogsTurn on/off logging
/groupGroup settings
/itembanBan an item
/projbanBan a projectile
/tilebanBan a tile
/regionRegion settings
/kickKicks a player
/muteMutes a player
/tempgroupAdd a temporary group to a player
/userinfoReveals information regarding a specific user
/annoy"You are now being annoyed."
/confuseConfuse a player
/rocketRocket a player
/fireworkLaunch a firework
/checkupdatesQueues an update-check
/offSaves and turns the server off, after which you will have to restart the server from the control-panel
/off-nosaveTurns off the server without saving, read above
/reloadReloads configuration settings
/restartRestarts the server
/serverpasswordSets or changes the server password
/versionShows the current version
/giveGive an item to a player
/itemGive yourself an item
/butcherButcher nearby NPCs
/renamenpcRename an NPC
/invadeIssue an invasion
/maxspawnsSets and shows maximum spawns
/spawnbossSpawns a specified boss
/spawnmobSpawns a specified monster
/spawnrateSets the spawn rate
/clearanglerClears the angler quest completion list
/homeTeleports you to your spawnpoint
/spawnTeleports you to the server spawnpoint
/tpTeleports a player to another player
/tphereTeleports a player to you
/tpnpcTeleports an NPC
/tpposTeleports to a specific position
/tpallowEnables teleportation protection
/expertEnables expert mode
/antibuildEnables anti-build
/bloodmoonGenerates a bloodmoon
/growGrows a plant
/dropmeteorDrops a meteorite
/eclipseStart an eclipse
/forcehalloweenForce halloween mode
/forcexmasForce christmas mode
/fullmoonGenerated a fullmoon
/hardmodeEnables hard mode
/protectspawnEnables or disables spawn protection
/sandstormStops or starts a sandstorm
/rainToggle rain on or off
/saveSave the server state
/setspawnSet server spawnpoint
/setdungeonSets dungeon's position
/settleSettles all server liquids
/timeDisplays current server time
/windSets wind speed
/worldReveals information regarding the world
/buffBuff yourself
/clearClear the chat
/gbuffGive a buff to a player
/godmodeEnables godmode for yourself
/healHeal yourself
/killKill a player
/meTalk in third person
/partyParty settings
/replyReplies to a whisper
/restREST settings
/slapSlap a player
/serverinfoDisplays information regarding the server
/warpWarp settings
/whisperWhisper a player
/aliasesAlias settings
/motdDisplay current Message Of The Day
/playingShows a list of current players
/rulesDisplay specified server rules