ClaudeForFoundationModels — Development skill for Claude Code

Claude for Foundation Models

Use Claude as a server-side language model through Apple's [Foundation Models](https://developer.apple.com/documentation/foundationmodels) framework. The package conforms Claude to the framework's `LanguageModel` protocol, so you drive it with the same `LanguageModelSession` API you use for Apple's on-device model — `respond(to:)`, streaming, guided generation, and tool calling all work the same way.

**Beta.** This package targets the Foundation Models server-side language model API introduced in the OS 27 betas. APIs may change before general availability.

Contents

• Requirements
• Installation
• Quick start
• Example
• Choosing a model
• Authentication
• Streaming
• Structured output
• Server-side tools
• Error handling
• What this package provides
• Support
• License

Requirements

• iOS 27, macOS 27, visionOS 27, or watchOS 27 (beta) — the OS releases whose Foundation Models framework supports server-side language models.
• Xcode 27 (beta).
• A credential: an App Attest client ID from the Anthropic console, or an API key for simulator development. See Authentication.

Installation

Add the package to your `Package.swift`:

dependencies: [
  .package(url: "https://github.com/anthropics/ClaudeForFoundationModels.git", from: "0.1.0")
]

Or in Xcode: **File ▸ Add Package Dependencies…** and enter the repository URL.

Then add `ClaudeForFoundationModels` to your target's dependencies and import it alongside `FoundationModels`:

import FoundationModels
import ClaudeForFoundationModels

Quick start

import FoundationModels
import ClaudeForFoundationModels

let model = ClaudeLanguageModel(
  name: .sonnet5,
  auth: .apiKey(ProcessInfo.proc