Kotlin Interface Map

The plugin world imports these host interfaces. Kotlin exposes them in pumpkin; for example, WIT boss-bar becomes pumpkin.BossBar. Each WIT link opens its source definition.

WIT definition	Generated Kotlin namespace	Purpose
logging	Logging	Server logging.
gui	Gui	GUI resources and their inventories.
scoreboard	Scoreboard	Scoreboard resources.
server	Server	Global server and player lookup.
text	Text	Text components.
command	Command	Command trees, senders, arguments, execution, and suggestions. commands manages callback IDs.
context	Context	Context.Context registration, server access, and plugin data folder.
i18n	I18n	Translation and locale support.
scheduler	Scheduler	Delayed/repeating tasks and cancellation. PumpkinPlugin.tasks manages both callback forms.
world	World	Worlds, blocks, entities, chunks, and generation. Custom AI and generators call back into PumpkinPlugin.
entity	Entity	Entity-related types exposed across the API.
boss-bar	BossBar	Boss bar types and resources.
forms	Forms	Bedrock forms.
java-dialogs	JavaDialogs	Java Edition dialogs.
status-effect	StatusEffect	Status effect types and instances.
block-entity	BlockEntity	Block entity types and resources.
ipc	Ipc	Send messages to another plugin; inbound messages use handleIpcMessage.
attributes	Attributes	Entity attributes and modifiers.
player	Player	Player resources and operations, including inventory access.
advancement	Advancement	Advancement definitions and progress.
recipe	Recipe	Recipe definitions and registration.
inventory	Inventory	Inventory and player-inventory resource operations.
datapack	Datapack	Datapack inspection and management.
enchantments	Enchantments	Enchantment types.
damage-types	DamageTypes	Damage types.
screens	Screens	Screen and container types.
statistics	Statistics	Player statistics categories and types.
display	Display	Display and interaction entities.
game-rules	GameRules	Game rule definitions and values.
game-events	GameEvents	Game event types.
potions	Potions	Potion types.
entity-statuses	EntityStatuses	Entity status and animation types.

WIT names as Kotlin definitions

The generated Kotlin names and types follow the WIT definitions:

WIT	Kotlin
context resource context	Context.Context; also aliased as PluginContext by the handwritten API
inventory resource inventory	Inventory.Inventory
event variant event	Event.Event
world resource world	World.World
u8, u16, u32, u64	UByte, UShort, UInt, ULong
s32, bool, string	Int, Boolean, String
list<u8>, option<T>	List<UByte>, nullable T?
result<T, E>	Kotlin Result<T> at the generated call boundary

WIT register-event-with-handle becomes context.registerEventWithHandle(handlerId, eventType, priority, blocking) and returns a ULong. WIT get-item: func(slot: u32) -> option<item-stack> becomes inventory.getItem(slot: UInt): ItemStack.ItemStack?. IDE completion shows the members in your API version.

These operations connect generated WIT calls to the Kotlin registration APIs:

WIT operation	Generated Kotlin call	Kotlin API
context.register-event-with-handle and unregister-event	context.registerEventWithHandle(id, type, priority, blocking) and context.unregisterEvent(registrationId)	events.listen(...) and EventSubscription.unregister()
command.execute-with-handler-id and context.register-command	command.executeWithHandlerId(id) then context.registerCommand(command, permission)	commands.register(...)
command-node.suggest-with-handler-id	node.suggestWithHandlerId(id)	commands.onSuggestions(...)
scheduler.schedule-delayed-task	Scheduler.scheduleDelayedTask(id, delayTicks)	tasks.afterTicks(...)
scheduler.schedule-repeating-task and cancel-task	Scheduler.scheduleRepeatingTask(id, delayTicks, periodTicks) and Scheduler.cancelTask(taskId)	tasks.everyTicks(...) and ScheduledTask.cancel()
mob.add-custom-ai-goal	mob.addCustomAiGoal(priority, goalId)	aiGoals.register(...)
world.set-chunk-generator	world.setChunkGenerator(generatorId)	chunkGenerators.set(...)
ipc.send-ipc-message	Ipc.sendIpcMessage(recipient, message)	Outbound IPC; the recipient uses ipc.onMessage(...)

The Kotlin API assigns handler IDs for its registration methods. Direct calls through generated bindings require you to manage those IDs.

Shared type interfaces

These interfaces define types used by host imports and plugin exports. They are not separate imports in the plugin world:

WIT definitions	Kotlin namespaces
common, uuid	Common, Uuid
biomes, sounds, particles	Biomes, Sounds, Particles
java-packets, bedrock-packets	JavaPackets, BedrockPackets
item-stack, data-components	ItemStack, DataComponents
permission, event, metadata, entity-types	Permission, Event, Metadata, EntityTypes

Resource methods such as Inventory.Inventory.getItem and setItem need no callback or handler ID. The callback reference covers operations that do.