ArLib

A utility datapack library for Minecraft 26.1+ (pack format 101).

It includes the following functionality: chat functions, player management, combat, world controls, math helpers, entity tools, inventory utilities, sound, and teleport functions.

And it also helps developers developing with logging,

All functions use macro parameters passed through arlib:input storage unless noted otherwise.

General usage pattern:

data merge storage arlib:input {param1:"value1", param2:"value2"}
function arlib:<category>/<name> with storage arlib:input

Logging Screenshot

Logging Chat Example

Documentation

Docs

Debug / Dev Logging

ArLib has a built-in debug logging system. Log messages are only shown when debug mode is enabled and only to players who have the arlib.debug tag.

Setup

# Enable debug logging
scoreboard players set #debug arlib.dev 1

# Show log messages for a player
tag @s add arlib.debug

# Hide log messages for a player
tag @s remove arlib.debug

# Disable debug logging entirely
scoreboard players set #debug arlib.dev 0

The ArLib "Loaded." message also only appears when debug is on.

Log functions

All log functions take a single message parameter.

chat/info - Aqua [INFO] prefix.

data merge storage arlib:input {message:"Player entered zone."}
function arlib:chat/info with storage arlib:input

chat/success - Green [OK] prefix.

data merge storage arlib:input {message:"Arena ready."}
function arlib:chat/success with storage arlib:input

chat/warn - Yellow [WARN] prefix.

data merge storage arlib:input {message:"Low on resources."}
function arlib:chat/warn with storage arlib:input

chat/error - Dark red [ERROR] prefix.

data merge storage arlib:input {message:"Target not found."}
function arlib:chat/error with storage arlib:input

Chat

chat/send - Send a formatted chat message to a specific target.

Param	Description
prefix	Tag shown in brackets, e.g. "INFO"
color	Color code for the prefix (0-f)
message	The message text
target	Player selector, e.g. "@a", "@s"

data merge storage arlib:input {prefix:"INFO", color:"6", message:"Hello!", target:"@a"}
function arlib:chat/send with storage arlib:input

chat/broadcast - Same as chat/send but always sends to all players. No target param needed.

Param	Description
prefix	Tag shown in brackets
color	Color code for the prefix (0-f)
message	The message text

data merge storage arlib:input {prefix:"SERVER", color:"b", message:"Restarting soon."}
function arlib:chat/broadcast with storage arlib:input

chat/title - Show a title and subtitle on screen.

Param	Description
target	Player selector
title	Main title text
subtitle	Subtitle text

data merge storage arlib:input {target:"@a", title:"Welcome!", subtitle:"Enjoy your stay."}
function arlib:chat/title with storage arlib:input

chat/actionbar - Show a message on the action bar (above the hotbar).

Param	Description
target	Player selector
message	The message text

data merge storage arlib:input {target:"@s", message:"Mana: 50/100"}
function arlib:chat/actionbar with storage arlib:input

chat/clear - Clear a player's chat by flooding it with blank lines.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@a"}
function arlib:chat/clear with storage arlib:input

Player

player/heal - Fully heals a player.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@s"}
function arlib:player/heal with storage arlib:input

player/feed - Fully restores food and saturation.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@s"}
function arlib:player/feed with storage arlib:input

player/clear_effects - Removes all potion effects.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@a"}
function arlib:player/clear_effects with storage arlib:input

player/freeze - Freeze or unfreeze a player by setting movement speed and jump strength to 0.

Param	Description
target	Player selector
state	"freeze" or "unfreeze"

data merge storage arlib:input {target:"@s", state:"freeze"}
function arlib:player/freeze with storage arlib:input

data merge storage arlib:input {target:"@s", state:"unfreeze"}
function arlib:player/freeze with storage arlib:input

Combat

combat/damage - Deal a specific amount of damage to a target. 1 = half a heart.

Param	Description
target	Player selector
amount	Damage amount (half hearts)

data merge storage arlib:input {target:"@p", amount:"6"}
function arlib:combat/damage with storage arlib:input

combat/set_health - Set a player's health to an exact value. Temporarily changes max health, heals, then restores max health to 20.

Param	Description
target	Player selector
health	Health value (1-20, 1 = half heart)

data merge storage arlib:input {target:"@s", health:"6"}
function arlib:combat/set_health with storage arlib:input

World

world/time_set - Set the world time using a named preset.

Param	Description
time	"day", "noon", "night", or "midnight"

data merge storage arlib:input {time:"noon"}
function arlib:world/time_set with storage arlib:input

world/weather_set - Set the weather.

Param	Description
weather	"clear", "rain", or "thunder"

data merge storage arlib:input {weather:"thunder"}
function arlib:world/weather_set with storage arlib:input

Time

time/is_day - Sets #is_day arlib.temp to 1 if daytime (0-12999 ticks), 0 otherwise. No parameters.

function arlib:time/is_day
execute if score #is_day arlib.temp matches 1 run say It's daytime!

time/is_night - Sets #is_night arlib.temp to 1 if nighttime (13000-23999 ticks), 0 otherwise. No parameters.

function arlib:time/is_night
execute if score #is_night arlib.temp matches 1 run function my_pack:night_logic

Math

All math functions operate on scoreboard values. Requires arlib:load to have run first.

math/clamp - Clamp a scoreboard value between a min and max.

Param	Description
target	Score holder, e.g. "@s" or "#score"
objective	Scoreboard objective name
min	Minimum value
max	Maximum value

data merge storage arlib:input {target:"@s", objective:"health", min:"0", max:"20"}
function arlib:math/clamp with storage arlib:input

math/abs - Set a scoreboard value to its absolute value.

Param	Description
target	Score holder
objective	Scoreboard objective name

scoreboard players set @s velocity -42
data merge storage arlib:input {target:"@s", objective:"velocity"}
function arlib:math/abs with storage arlib:input
# @s velocity is now 42

math/random - Generate a random number and store it in a scoreboard.

Param	Description
target	Score holder
objective	Scoreboard objective name
min	Minimum value (inclusive)
max	Maximum value (inclusive)

data merge storage arlib:input {target:"@s", objective:"dice", min:"1", max:"6"}
function arlib:math/random with storage arlib:input

Entity

entity/kill_type - Kill all entities of a given type.

Param	Description
type	Entity type, e.g. "minecraft:zombie"

data merge storage arlib:input {type:"minecraft:creeper"}
function arlib:entity/kill_type with storage arlib:input

entity/count_type - Count all entities of a type and store the result in a scoreboard.

Param	Description
type	Entity type
target	Score holder for the result
objective	Scoreboard objective

data merge storage arlib:input {type:"minecraft:zombie", target:"#count", objective:"arlib.temp"}
function arlib:entity/count_type with storage arlib:input
execute if score #count arlib.temp matches 10.. run say Too many zombies!

entity/freeze_all - Set or remove NoAI on all entities of a type.

Param	Description
type	Entity type
noai	"1b" to freeze, "0b" to unfreeze

data merge storage arlib:input {type:"minecraft:creeper", noai:"1b"}
function arlib:entity/freeze_all with storage arlib:input

entity/glow - Give the glowing effect to all entities of a type.

Param	Description
type	Entity type
duration	Duration in seconds, or "infinite"

data merge storage arlib:input {type:"minecraft:zombie", duration:"10"}
function arlib:entity/glow with storage arlib:input

entity/glow_remove - Remove the glowing effect from all entities of a type.

Param	Description
type	Entity type

data merge storage arlib:input {type:"minecraft:creeper"}
function arlib:entity/glow_remove with storage arlib:input

Inventory

inventory/clear_slot - Clear a specific inventory slot by replacing it with air.

Param	Description
target	Player selector
slot	Slot name (see below)

Common slots: container.0 through container.8 (hotbar), container.9 through container.35 (main inventory), armor.head, armor.chest, armor.legs, armor.feet, weapon.offhand.

data merge storage arlib:input {target:"@s", slot:"container.0"}
function arlib:inventory/clear_slot with storage arlib:input

inventory/give_safe - Give an item only if the player has at least one empty inventory slot. Shows a warning if full.

Param	Description
target	Player selector
item	Item ID, e.g. "minecraft:diamond"
count	Amount to give

data merge storage arlib:input {target:"@s", item:"minecraft:golden_apple", count:"3"}
function arlib:inventory/give_safe with storage arlib:input

inventory/swap_offhand - Swap a player's mainhand and offhand items.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@s"}
function arlib:inventory/swap_offhand with storage arlib:input

Sound

sound/play - Play a sound to a target. Uses master channel, volume 1, pitch 1.

Param	Description
target	Player selector
sound	Sound ID, e.g. "minecraft:entity.experience_orb.pickup"

data merge storage arlib:input {target:"@s", sound:"minecraft:block.note_block.pling"}
function arlib:sound/play with storage arlib:input

sound/alert - Play a short high-pitched pling sound to a player.

Param	Description
target	Player selector

data merge storage arlib:input {target:"@a"}
function arlib:sound/alert with storage arlib:input

Teleport

tp/save - Save the executing player's current position under a named slot. Must run as the player (as @s).

Param	Description
name	Name for the waypoint

data merge storage arlib:input {name:"home"}
execute as @s run function arlib:tp/save with storage arlib:input

tp/load - Teleport the executing player to a previously saved position. Must run as the player.

Param	Description
name	Name of the saved waypoint

data merge storage arlib:input {name:"home"}
execute as @s run function arlib:tp/load with storage arlib:input

tp/swap - Swap the positions of two players.

Param	Description
player1	First player selector
player2	Second player selector

data merge storage arlib:input {player1:"@a[tag=red]", player2:"@a[tag=blue]"}
function arlib:tp/swap with storage arlib:input