Best Practices for Designing New Ephemeral CLI Programs for the Agentic Era: A Proposal

This proposal examines the growing role of command-line interfaces (CLI) as the default local interaction protocol for AI agents in sandboxed and developer environments. It argues that, when local execution is available, CLI often offers better efficiency, composability, and reliability than remote protocol-based alternatives such as MCP. The paper identifies a gap in current practice: while much effort has gone into exposing existing software through CLI, there is little guidance on designing new, task-specific, ephemeral CLI tools for agent workflows. The document therefore proposes distilling a practical set of best practices for building such agent-native command-line programs from scratch.