# Codex Opinion

> Second opinion from OpenAI Codex — you, Claude, and Codex in the loop. Invoke /codex-opinion:codex-opinion, or naturally via phrases like "ask codex," "second opinion," "another perspective," "codex weigh in," "reconcile with codex."

- Skill: `ehzawad/codex-opinion` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add ehzawad/codex-opinion`
- Raw SKILL.md: https://api.skillmd.com/api/skills/ehzawad/codex-opinion/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: ehzawad (https://skillmd.com/u/ehzawad)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/ehzawad/codex-opinion

---


# Codex Second Opinion

Get a second opinion from OpenAI Codex on your current work. Codex uses your configured model and settings.

## How to call

Call with your context on stdin. A Codex call takes as long as the work takes; use Bash `run_in_background: true` and wait for Claude Code's completion notification instead of sleep-polling.

```bash
echo "<gathered context>" | python3 ${CLAUDE_PLUGIN_ROOT}/skills/codex-opinion/scripts/ask_codex.py
```

The script bookends stdin with a short default review directive. Pass a positional arg to override it, or `--no-default-instruction` to skip the wrapper entirely.

## Building the context

If there are uncommitted changes:

```bash
git diff HEAD | python3 ${CLAUDE_PLUGIN_ROOT}/skills/codex-opinion/scripts/ask_codex.py
```

If there are also untracked files that matter, include them (with binary/size guards):

```bash
{ git diff HEAD
  git ls-files --others --exclude-standard | while IFS= read -r f; do
      file --mime "$f" | grep -q 'charset=binary' && continue
      [ $(wc -c <"$f") -gt 32768 ] && continue
      printf '\n=== %s ===\n' "$f"
      cat "$f"
  done
} | python3 ${CLAUDE_PLUGIN_ROOT}/skills/codex-opinion/scripts/ask_codex.py
```

If the tree is clean, gather context yourself:

```bash
echo "Review this codebase. Key files: ..." | python3 ${CLAUDE_PLUGIN_ROOT}/skills/codex-opinion/scripts/ask_codex.py
```

With a custom instruction (from user text after `/codex-opinion:codex-opinion`):

```bash
echo "<context>" | python3 ${CLAUDE_PLUGIN_ROOT}/skills/codex-opinion/scripts/ask_codex.py "user's instruction"
```

**Never pipe an empty string.** If `git diff HEAD` would be empty, use echo with gathered context instead.

## Session continuity

One Codex session per project, persisted across Claude Code sessions. Follow-up calls resume the prior Codex thread so it keeps its accumulated codebase knowledge. Reframe when the task shifts so prior framing doesn't bias later turns. If the session has expired server-side, the script logs a notice and starts fresh.

Set `CODEX_OPINION_SESSION_KEY` before launching Claude Code to isolate a session from the project-wide thread.

## After Codex responds

Reconcile Codex's findings with your own read, then tell the user what changed, what you accept, what you challenge, and what remains uncertain.

Multi-turn is available when a reply warrants follow-up (Claude → Codex → Claude → Codex → reconcile); default is single-turn.