Foundation Models

Foundation Models

Integrate Apple's on-device LLM into your apps for privacy-preserving AI features. Companion references: safety-and-guardrails.md (model limits, prompt design, the four-layer safety stack), models-and-agents.md (Private Cloud Compute, LanguageModel protocol, vision input, DynamicProfile agentic sessions — the iOS 27 wave), and utilities-package.md (Apple's open-source utilities package: OpenAI-compatible endpoints, just-in-time Skills, history compression).

When This Skill Activates

• User wants AI text generation features
• User needs structured data from natural language
• User asks about prompting or LLM integration
• User wants to implement AI assistants or agentic features (tool loops, multi-profile sessions)
• User needs content summarization or extraction
• User asks about Private Cloud Compute, guardrails, or model safety

Model Fit — Check Before Building

The on-device model is ~3B parameters (2-bit quantized): built for summarization, extraction, classification, tagging, revision, short chat — not math, code generation, facts, or world knowledge (WWDC25 248). For capability boundaries, prompt-design rules, and the safety stack, read safety-and-guardrails.md first. For anything bigger, PrivateCloudComputeLanguageModel (32k context, reasoning) and third-party backends are in models-and-agents.md.

Quick Start

1. Check Availability

import FoundationModels

struct IntelligentView: View {
    private var model = SystemLanguageModel.default

    var body: some View {
        switch model.availability {
        case .available:
            ContentView()
        case .unavailable(.deviceNotEligible):
            UnsupportedDeviceView()
        case .unavailable(.appleIntelligenceNotEnabled):
            EnableIntelligenceView()
        case .unavailable(.modelNotReady):
            ModelDownloadingView()
        case .unavailable(let reason):
            ErrorView(reason: reason)
        }