Code analysis of iOS 27 and macOS Golden Gate has revealed private frameworks indicating that Apple has designed its new Siri architecture to work with third-party AI models at a significant level.

One mechanism, called Model Delegation, allows models such as Claude to function as a Siri extension, similar to the existing ChatGPT extension. In a demonstration, a user can select Claude via a contextual menu to perform tasks like setting reminders in the Apple Reminders app. In such scenarios, Claude interprets the natural language request and hands the execution back to Siri if system feature access is required.

Furthermore, a protocol within "Model Manager Services" appears to allow Apple's own server-side Siri model to be replaced by other models, such as GPT-5.6. In this setup, the third-party model receives Apple's Siri planner prompts and tool definitions, enabling it to request system actions and formulate answers that Siri presents through its own interface and voice.

While the current "Ask..." implementation is limited to the ChatGPT extension in the macOS 27 Golden Gate Release Candidate, the architecture demonstrates extensive engineering for future model interoperability. Analysts suggest that the European Union's Digital Markets Act, which requires Apple to provide third parties effective access to iOS features, may have influenced this architectural direction.

Sources: