Apple is investing heavily in making Siri AI a centerpiece of its product ecosystem, and its recent Surprise and Shine event indicated that the redesigned voice assistant will be a major selling point for the new iPhone 18 Pro.
However, a post on X from pdfu, a frequent source of leaks involving code for upcoming iOS and MacOS releases, suggests that the technology company may not be keeping rival AI systems away from its hardware. The post claims that Apple’s AI will work closely with third-party models, including OpenAI’s ChatGPT and Anthropic’s Claude, and could even allow certain GPT models to replace Siri as the preferred on-device agent.
Representatives for Apple, OpenAI and Anthropic did not immediately reply to requests for comment.
The newest private frameworks allegedly leaked for iOS 27 and MacOS Golden Gate reportedly incorporate Claude models into a model delegation feature. This would let Siri AI users ask Apple’s model to pass a task on to another AI agent.
In a video shared by pdfu on X, Siri forwards a request to Claude to create a reminder in the Reminders app. Claude effectively acts as the on-device AI in the demonstration, while Siri serves as the middleman. Requests that need access to Apple’s proprietary system information are handled by Siri AI instead.
The footage also demonstrated a more advanced app extension capable of fully replacing Apple’s Siri AI model with another large language model. Through the model manager service in the private framework, pdfu successfully ran GPT-5.6 using Siri’s stored information to complete requests through Siri’s interface and voice controls.
In the video, GPT-5.6 searches emails stored on the device, identifies relevant details in the inbox and uses the text to send messages through the iMessages app. Information that would normally pass through Siri AI can be recorded in OpenAI’s web interface and accessed later on another platform.
Is Apple voluntarily dismantling parts of its walled garden? Probably not. The European Union’s Digital Markets Act, which obliges Apple to provide third-party developers with equal access to its hardware and software capabilities, has played a major role in shaping the rollout of its latest operating system updates.
The law specifically addressed Siri AI and Google’s Gemini AI, determining that phone manufacturers must allow third-party AI developers to access on-device software updates in the future to curb market gatekeeping.
Although Apple is not welcoming outside AI companies out of generosity, the development represents significant news for OpenAI and Anthropic, the organizations behind ChatGPT and Claude.
Both companies are competing to build more sophisticated models and demonstrate their value to the public within a largely unregulated marketplace.
With potentially highly profitable IPOs for both businesses on the horizon, OpenAI and Anthropic are likely to keep pursuing access to the enormous market of iPhone users in the United States.