Conleash: Lattice-Based Authorization for MCP Tool Invocations

Conleash, a novel middleware system, tackles consent fatigue within the Model Context Protocol (MCP) by implementing boundary-scoped authorization. It incorporates a risk lattice for automatic approval of safe calls, a policy engine that allows users to define invariants, and a refinement loop that transforms user choices into reusable rules. Tested against 984 real-world traces, Conleash demonstrated an impressive 98.2% accuracy, successfully identified 99.4% of escalations, and introduced a mere 8.2 ms overhead. In a user study involving 16 participants, Conleash's scoped permissions were favored over conventional approaches, with users noting increased trust and fewer prompts.