Apple's siri architecture opens door for third-party AI models

Developer pdfu uncovered code in iOS 27 and macOS Golden Gate that reveals Apple's new Siri AI architecture is designed to support third-party models like Claude and GPT-5.6. The system allows these models to integrate into Siri through two mechanisms: 'Model Delegation' and 'Model Management Service.' Model Delegation lets third-party models like Claude handle specific tasks, such as creating reminders or CSV files, while passing execution back to Siri for system functions. The 'Model Management Service' goes further, enabling users to replace Siri's on-device model entirely with external models, allowing ChatGPT to take over Siri's planning and tool definitions. Despite these capabilities, the features are not yet available to users. The 'Ask…' function is currently limited to the ChatGPT extension in macOS 27, while Claude remains inaccessible. Apple has not yet authorized third-party model delegation. However, the code suggests Apple has made significant engineering progress toward future model interoperability. The EU's Digital Markets Act is believed to be a key driver behind these changes, requiring Apple to provide equal access to its hardware and software functions for third parties, including Siri.