CLI over MCP: a small Chrome DevTools experiment in Copilot CLI

I ran the same browser smoke task through two paths: direct Chrome DevTools MCP and a custom CLI skill around mcp2cli. In GitHub Copilot CLI with gpt-5.3-codex-medium, direct Chrome DevTools MCP added about 5k tokens of upfront context before the agent did any work. The runtime table is too small and too noisy to rank the tools. The useful question is where the agent pays to discover the browser-control surface. mcp2cli README says it can “Save 96-99% of the tokens wasted on tool schemas ever...