CLI coding agents are no longer passive text processors: in agent mode they execute shell commands, edit files, and make network requests, yet they inherit the user's full permissions with no sandbox and no undo. Security for agent runtimes therefore has to be architectural (container, scoped mounts, proxy) rather than aspirational policy.
Execution privilege is the whole safety boundary: any coding agent can run destructive commands or exfiltrate data, so the boundary must be designed into the runtime rather than being left to the agent's good behavior.
Any system that gives an LLM tool execution on a user's machine should treat the runtime as untrusted and separate it from the host and from ambient credentials.
CLI agents run with the full privileges of the user executing them, meaning no sandbox and no undo when destructive commands are issued.
Security must be architectural, not aspirational.