A hidden feature suggests Apple might let you replace Siri with Claude or ChatGPT in iPhone and macOS

Looking ahead: Apple has reportedly designed the new Siri architecture with a private Extensions Framework that allows users to set third-party AI models, such as Claude, as the default AI for iPhones and Macs. The feature reportedly works with iOS 27 and macOS Golden Gate, both of which are now rolling out to compatible iPhones and Macs. The Extensions Framework offers a dedicated Settings area that lets users choose their preferred backend model to provide Siri with writing tools and image generation capabilities. Siri would act as an intermediary, receiving voice commands or text input from the user and routing them to the selected model provider. Coder and reverse engineer pdfu, also known as mactracker on MacRumors Forums, claims that Apple has incorporated two systems to integrate third-party AI into its hardware. The first reportedly uses the Model Delegation API, which lets third-party models like Claude operate as a Siri extension, similar to the built-in ChatGPT extension in Siri's model picker. - pdfu (@itspdfu) September 13, 2026 To demonstrate the feature in action, the tipster opened the "Search or Ask" bar on their Mac and selected Claude from the "Ask" menu. They then asked Siri to ask Claude to create a reminder in the Reminders app. However, since the task required access to a system app with potential privacy concerns, it was completed by Siri after Claude processed and interpreted the request. In contrast, Claude completes certain tasks by itself when Siri is unable to act on those requests. One such demonstration seems to show Claude creating a CSV file after receiving a natural language voice prompt because Siri AI is still unable to process CSVs and certain other file formats. The second system has an even larger scope, allowing an inference provider in the "Model Manager Services" component in iOS 27 and macOS Golden Gate to replace the server-side Siri AI with third-party services. While the tipster identified GPT-5.6 as a provider, Apple has yet to confirm the tie-up. The tipster explained that the technology allows the third-party AI model to process the prompt and prepare the answers before relaying them to Siri, which then presents them using its own GUI or voice. If it's a task rather than a query, the third-party model processes the request and hands it over to Siri, which then executes the task according to the user's instructions. It is worth noting that although the model selection feature is part of iOS 27 and macOS Golden Gate, it isn't available to users just yet. However, with the EU's Digital Markets Act specifically mandating that built-in AI chatbots in computing devices should allow users the choice of multiple models, it should only be a matter of time before Apple officially opens Siri up to third-party models.