The MCP conversation is moving fast, but the research signal is already clearer than the hype. Recent papers on audits, ecosystem attacks, malicious tools, and enterprise mitigations now point to the same conclusion: tool interoperability without policy discipline is fragile by default.
Tool-using AI apps are powerful, but the real risk is not the model alone. It is the invisible handoff between prompts, tools, permissions, and human approval. This playbook maps the boundary correctly.
User prompts are no longer the only place agents get poisoned. New benchmark work and recent security papers show that skill files, tool instructions, and agent-side context packages are now a serious injection surface.