Abstract: The embedding of system-level agents into mobile terminals marks an ontological transformation of the human-computer interaction (HCI) paradigm from “information intermediary” to “action agency”. By acquiring simulated input permissions at the underlying level of the operating system, this technology achieves penetration of the application sandbox isolation mechanism and the takeover of cross-application action rights, thereby leading to the deconstruction of the human-embodied relationship and the concealment of human subjectivity. Algorithms are no longer limited to generating fake content; driven by the synergy of permission capture, intent deviation, and execution black boxes, they generate “simulacra actions” that may violate the subject’s original intentions but possess legitimate forms. This evolution induces a dual alienation of instrumental rationality and value rationality, leading the foundation of digital contracts and trust systems to an ontological crisis. In view of this, The logic of responsibility reconstruction should shift from unilateral technical blocking to multilateral protocol co-construction. By establishing the “Turing Isolation” identification mechanism, defining the “Return to Embodiment” bottom line for critical interaction nodes, and promoting the standardization of the A2A Protocol, a credible responsibility governance paradigm can be reconstructed between algorithmic automation and human autonomy.