grey-rso — Second Opinion MCP (Rust)

An MCP server that lets your AI coding assistant consult a different, strong coding assistant, when it needs a fresh perspective.

It delegates to locally installed CLI agent harnesses, enabling the subagents to use full power of their tooling: search, explore, inspect etc.

When your agent is stuck or you want a sanity check, just say "ask gemini", "ask codex", "ask claude", or "ask kilo" and it queries the other model with the relevant files as context.

How does it work

The MCP tool exposes a single consult tool. The caller picks one of four short aliases — gemini, claude, codex, kilo — and the server maps that alias to an actual model name via a config file, then shells out to the corresponding CLI.

This keeps the MCP interface minimal and spends as little of your tokens as possible, when not used.

Quick start

Register with your cli agents (partial registration is fine):

cargo install grey-rso
claude mcp add --scope user grey-rso -- grey-rso
gemini mcp add --scope user grey-rso grey-rso
codex mcp add grey-rso -- grey-rso
kilo mcp add grey-rso grey-rso

Details

See DETAILS.md for slash command examples, skill setup, and development instructions.