Apple's Siri AI Can Be Swapped Out for Claude, ChatGPT, Code Shows

Code sleuth "pdfu" uncovered iOS 27 and macOS Golden Gate private frameworks showing that Apple has designed its new Siri architecture to work with third-party AI models at what appears to be a surprisingly deep level.

One mechanism, called Model Delegation, allows Claude to appear as a Siri extension in the same way as the existing built-in ChatGPT extension. In pdfu's video shared on X, the macOS user opens the "Search or Ask" bar and picks Claude as the AI model through an "Ask..." contextual menu. After enabling the Claude extension, the user asks Siri to "Ask Claude" to set a reminder in Apple's Reminders app; Claude interprets the natural-language reminder request and Siri then creates the reminder — implying that when a request needs an Apple system feature, Claude hands the task back to Siri. In another example, Claude appears in a Siri app conversation window receiving a request to create a CSV file — something Siri itself cannot do — and successfully returning the result.

The second, more intriguing protocol demonstrated in the video appears to go considerably further. An inference provider in "Model Manager Services" apparently lets Apple's own server-side Siri model be completely replaced by another model, such as GPT-5.6. In this setup, ChatGPT receives Apple's Siri planner prompt and tool definitions, enabling it to request system actions, receive the resulting personal data, and formulate an answer that Siri presents using its own interface and voice. The demo shows an app extension replacing Siri AI's server model with GPT-5.6 Terra via the Inference Providing protocol: the user asks the ChatGPT model inside the Siri app to find emails about a specific topic, summarize their contents and action points, then send a message to a person in their contacts via the Messages app — and the response is shown as logged in OpenAI's platform web interface.

The EU's Digital Markets Act may have helped shape Apple's approach, since it requires Apple to give third parties effective access to iOS hardware and software features available to Apple's own services, and the European Commission has said this principle extends to Siri. For now, the "Ask..." implementation is limited to the ChatGPT extension in the macOS 27 Golden Gate Release Candidate (effectively the final version, set to be released later that day), so Claude is not yet available, and Apple has not yet opened the model delegation entitlement to third parties.