@techreport{das-cross-platform-ai-interoperability-00, number = {draft-das-cross-platform-ai-interoperability-00}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-das-cross-platform-ai-interoperability/00/}, author = {Sangam Das}, title = {{Secure AI Execution-Finality for iOS, Android, and Cross-Platform AI Agents, Part 2: Secure iOS and Android AI Tool Interoperability}}, pagetotal = 439, year = 2026, month = oct, day = 26, abstract = {AI assistants and third-party AI tools now act across the Apple and Google ecosystems. Apple Siri invokes app actions through App Intents and Shortcuts, Google Gemini acts through Android intents and app integrations, and agents from many vendors reach the same accounts from iOS, iPadOS, macOS, Android, Windows, Linux, cloud APIs, and connected devices. Each hop crosses a different permission, sandbox, credential, identity, and hardware trust model. A prompt-injected, replayed, or redirected tool call can then export a file, send a payment, change data, or operate a device in a way that differs from what the user approved, and app permissions, Keychain or Android Keystore credentials, and OAuth tokens do not by themselves prove that the executed operation matches the approved one. This document, Part 2 of a twelve-part series, specifies how to carry authority across platforms without letting a platform permission become final authority. Platform-specific adapters for iOS and Android translate qualified app, user, device, and key evidence into a protected canonical effect descriptor; the AI tool's proposed action remains non-effective; operation-scoped, non-bearer authorization resists replay and redirection; and the receiving Finality Sink independently reconstructs the actual pending operation, checks resource identity, aliases, and redirects, fences stale devices after cross-device handoff, and fails closed on any mismatch. Reference data models, pseudocode, a state machine, six threat models, and twenty reproducible validation tests are included. Part 1 of the series defines the shared terminology and common workflows. The document relates these mechanisms to OAuth 2.0 Rich Authorization Requests and Demonstrating Proof of Possession (DPoP); Workload Identity in Multi-System Environments (WIMSE); Remote ATtestation procedureS (RATS); CBOR Object Signing and Encryption (COSE); Authentication and Authorization for Constrained Environments (ACE); Supply Chain Integrity, Transparency, and Trust (SCITT); and HTTP redirection and conditional requests. It identifies discussion points for these groups and for Security Area dispatch, without claiming working-group adoption or IETF consensus. Industry alignment covers Apple iOS, iPadOS, and macOS with Siri, App Intents, and Shortcuts; Google Android with Intents, Binder, and Android Keystore; Google Gemini; Samsung Bixby; Microsoft Windows and Azure agent governance; agent platforms from OpenAI, Anthropic, and Meta; NVIDIA, Qualcomm, Arm, and Huawei hardware; and payments, telecommunications, and robotics. Product names are illustrative and imply no endorsement or implementation by any vendor. For the EU Artificial Intelligence Act (Regulation (EU) 2024/1689), operation- level evidence and fail-closed cross-platform enforcement can help providers and deployers address risk-management, record-keeping, human-oversight, and robustness and cybersecurity requirements where those obligations apply; this is a technical mapping, not a conformity claim or legal advice.}, }