SystemLanguageModel

Represents the on-device Foundation Models language model. Provides availability checking and model configuration.

Constructor

new SystemLanguageModel(options?: {
  useCase?: SystemLanguageModelUseCase;
  guardrails?: SystemLanguageModelGuardrails;
})

Parameter	Default	Description
useCase	GENERAL	Model use case
guardrails	DEFAULT	Guardrail configuration

Methods

isAvailable()

Synchronously checks if the model is ready.

isAvailable(): AvailabilityResult

Returns { available: true } or { available: false, reason: SystemLanguageModelUnavailableReason }.

waitUntilAvailable()

Polls until the model is available or the timeout expires.

waitUntilAvailable(timeoutMs?: number): Promise<AvailabilityResult>

Parameter	Default	Description
timeoutMs	30000	Maximum wait time in milliseconds

dispose()

Releases the native model reference.

dispose(): void

Enums

SystemLanguageModelUseCase

Value	Description
GENERAL	General-purpose generation
CONTENT_TAGGING	Classification and labeling

SystemLanguageModelGuardrails

Value	Description
DEFAULT	Standard content safety guardrails

SystemLanguageModelUnavailableReason

Value	Description
APPLE_INTELLIGENCE_NOT_ENABLED	Apple Intelligence is off
MODEL_NOT_READY	Model assets still downloading
DEVICE_NOT_ELIGIBLE	Hardware not supported

Types

AvailabilityResult

type AvailabilityResult =
  | { available: true }
  | { available: false; reason: SystemLanguageModelUnavailableReason };