Nick Baumann: The Best Tools for Codex Are Bespoke CLIs

Nick Baumann isn't chasing MCP or the next protocol. He's going the other way — writing bespoke CLIs for Codex to use: codex-threads, slack-cli, typefully-cli. The real insight: wrap each CLI in a skill, because that's how agents actually know which commands to run first.

Karpathy: CLIs Are the Native Interface for AI Agents — Legacy Tech Becomes the Ultimate On-Ramp

Karpathy argues that CLIs are the most natural interface for AI agents — precisely because they're 'legacy' tech. Text in, text out. He demos Claude building a Polymarket terminal dashboard in 3 minutes via CLI, then drops the mic: every product should ask itself — can agents access and use it? CLI, MCP, markdown docs. It's 2026. Build. For. Agents.

Simon Willison: CLI Tools Beat MCP — Less Tokens, Zero Dependencies, LLMs Already Know How

Simon Willison doubles down on his stance: CLI tools beat MCP in almost every scenario for coding agents. Lower token cost, zero extra dependencies, and LLMs natively know how to call --help. Anthropic themselves proposed a 'third way' with code-execution-with-MCP, acknowledging MCP's token waste problem. This article breaks down the full MCP vs CLI trade-off, including a real-world case study from the ShroomDog team.