second-opinionlisted

# second-opinion Get an **independent** model to attack the current work. The value is uncorrelated failure: Codex/GPT was trained differently than Claude, so it catches blind spots Claude systematically shares with itself. This is adversarial review, **not** consensus voting — a second model agreeing means little (correlated priors); a second model finding a real hole is the whole point. Claude stays the driver. Codex is an on-call consultant invoked as a subprocess. ## GATE — don't fire on routine work Only worth the round-trip when the work is **high-stakes or hard to reverse**: a security/money path, a migration, a tricky invariant or proof, a load-bearing refactor, a claim that's expensive if wrong. Routine CRUD, config tweaks, obvious fixes → skip it, say so in one line, move on. If the user invoked this explicitly, honor it regardless of stakes. ## Preflight 1. `command -v codex` — if missing, stop and tell the user: `npm i -g @openai/codex`, then either `codex login` (ChatGPT account) or set `OPENAI_API_KEY` in your environment. 2. First run only: `codex exec --help | head -30` to confirm the flag names below match the installed version, and adapt if they drifted. ## Run Default target is the uncommitted working diff. Let Codex read the repo itself: ``` codex exec --sandbox read-only "You are an adversarial code reviewer. Review the uncommitted changes (run 'git diff' and 'git diff --staged') in this repo. Hunt ONLY for: correctness bugs, wrong assu