The host API is accessed through the host global. Like so: host:isFlying()

Functions in the host API aren't synced, meaning to be useful in multiplayer their information will need to be synced via pings.

isHost

Returns true if this instance of the script is running on host

Player Data

isJumping

Checks if the jump key is being pressed.

isFlying

Checks if the player is currently creative flying

isContainerOpen

Checks if the host has a container screen opened

getAir

Gets the remaining amount of air of the player. From 300 to -19, whenever you take damage from drowning it sets back to 0. Water breathing freezes the value when underwater. Respiration slows down how quickly the number goes down.

getSlot(integer or string)

Gets an ItemStack for the item in the given slot

The slot is either their numerical id (0 indexed) or the slot string, as used in the /item command

For the numerical id, 0-8 are the hotbar, 9-35 are the rest of the inventory starting from the top left slot, 99 is the offhand, and 100-103 are the armor slots from the boots to the helmet. player:getItem() is a better alternative for getting equipment slots.

setSlot(slot,item)

Sets a slot with an ItemStack

The slot is either their numerical id (0 indexed) or the slot string, as used in the /item command

Slot -1 uses the first available slot

Only runs for creative mode

getScreenSlot(slot)

Gets the item in a screen slot

The slot is either their numerical id (0 indexed) or the slot string, as used in the /item command

If the player is not currently in a screen, the screen has no slots, or the slot index is greater than the maximum, returns nil

getScreenSlotCount

Gets the number of slots in the screen the player is currently in

If the player is not currently in a screen or the screen has no slots, returns nil

getScreen

Gets the class name of the screen the player is currently on. Class names are slightly obfuscated by Minecraft's code and will return a string ending in numbers that are the class' id. A list of class ids can b found in GS' VSCode docs, or you can use a log to get the name of the screen you're accessing.

If the player is not currently in a screen, returns nil

getStatusEffects

Returns a table of all of the player's status effects

The table contains sub-tables, each of which contains the name, amplifier, duration, and particle visibility of each status effect. To access a sub table index the effect table with the sub-table's name. Re the example below: effect.name

for _, effect in pairs(host:getStatusEffects()) do
    logTable(effect)
end

getAttackCharge

Returns a fraction (0 to 1) of the charge of the player attack

If less than 1, every attack will result result in a weak attack

getReachDistance

Returns the current reach distance of the player

getPickBlock

Returns the current targeted block set by the client

Returns a vararg of the block, the hit position and the block face the hit collided

getPickEntity

Returns the current targeted entity set by the client

Chat

isChatOpen

Checks if the host has the chat screen opened

sendChatCommand(string)

Sends the given command in the chat

setChatMessage(integer,string,vec3)

Modifies a chat message with the given text

Takes an index, were 1 means the last message on chat

Setting the message to nil will effectively remove it from the chat

sendChatMessage

Sends the given message in the chat

getChatMessage(integer)

Returns a table with information about a chat message

Takes an index, were 1 means the last message on chat

appendChatHistory(string)

Appends the message on the recent chat history

setChatText

Sets the text currently being typed in the chat window to the given string

getChatText

Gets the text that is currently being typed into the chat window

setChatColor(vec3)

Sets the color of the text that is currently being typed into the chat window

getChatColor

Gets the chat window text color

isChatVerified

Presumably gets if the messages being sent are verified by the Minecraft server (speculation)

Other

swingArm(bool)

Animates swinging the player's arm

If the boolean is true, then the offhand is the one that swings

setTitle(string)

Sets the current title to the given text

The text is given as json

setSubtitle(string)

Sets the current subtitle to the given text The text is given as json

setActionbar(string,bool)

Sets the action bar message to the given text

The boolean parameter defaults to false and sets if the text will be animated

setTitleTimes(vec3)

Sets the duration of the title on the screen, also its fade-in and fade-out durations.

The inputs for the vec3 are order like-so: (fadeInTime, stayTime, fadeOutTime)

clearTitle

Clears the current title from the GUI

setUnlockCursor(bool)

Toggles locking of your cursor, letting you move it freely on the screen instead of it controlling your player's rotation

isCursorUnlocked

Checks if the cursor is currently unlocked

Only responds to your own changes in script, not anything done by Minecraft

screenshot

Takes a screenshot from the current screen and returns a Texture of it

setClipboard

Sets the clipboard text

getClipboard

Gets the text from the clipboard

isAvatarUploaded

Checks if this avatar is currently uploaded