iOS/macOS 27: Siri can swap in Claude or ChatGPT as backend

On 14 Sep 2026 MacRumors (via code sleuth pdfu) reported that iOS 27 and macOS Golden Gate include private frameworks for deep third-party Siri backends. Model Delegation lets Claude appear in Siri’s Ask… menu like the built-in ChatGPT extension, handing system actions (e.g. Reminders) back to Siri; a second Inference Provider path in Model Manager Services can replace Apple’s server-side Siri model entirely so GPT‑5.6 receives Apple’s planner prompt and tool definitions. Demos show Claude creating CSVs Siri can’t, and ChatGPT summarizing mail then messaging contacts via Siri’s UI. Ask… is ChatGPT-only in the Golden Gate RC; the model-delegation entitlement is not yet open to third parties. Ars Technica (14 Sep) covered the full OS ship: Siri AI is live in iOS/macOS 27 with Apple’s AFM 3 model family alongside the third-party backend option.