codex

A command that asks OpenAI’s Codex CLI, a command-line coding agent, for a second opinion on a question or proposed change.

In plain words
What is it for?
Use it for code reviews, design and architecture reviews, investigations, and general technical questions when the required Codex CLI setup is available.
Why use it?
It adds an independent review of code, plans, architecture, or other technical questions when another perspective would help.

Command

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/pablomarin/claude-codex-forge/codex
Clone the repo
git clone --depth 1 https://github.com/pablomarin/claude-codex-forge
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 7,478 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.07478
Opus 5 $0.00000 $0.03739
Sonnet 5 $0.00000 $0.01496
Haiku 4.5 $0.00000 $0.00748

Measured 2d ago against content hash 96c711385bbe, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codex scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

commands/codex.md · 392 lines

How it starts

The opening of the file, as written. The whole thing — 392 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Codex Second Opinion

Get a second opinion from OpenAI's Codex CLI. Use for code reviews, design plan reviews, architecture feedback, or general questions. For multi-perspective analysis with 5 advisors, use /council <question> instead.


Prerequisites

  • Codex CLI installed: npm i -g @openai/codex or brew install --cask codex
  • Codex authenticated: codex login (requires ChatGPT Plus/Pro/Business or API key)
  • Verify: codex --version (requires v0.124.0+ — every mode here captures the clean verdict with --output-last-message, stable since 0.124 per openai/codex#4644)

Use .claude/hooks/lib/codex-pty.sh exec for all Codex invocations (Windows: .claude/hooks/lib/codex-pty.ps1 exec). Do not call bare codex exec from Claude Code.


Mode Detection

Analyze $ARGUMENTS to determine the mode:

  • Code Review Mode: Arguments match review-related keywords — "review code", "code review", "review changes", "review diff", "review PR", or bare "review"
  • Design Review Mode: Arguments reference a plan, design, or architecture — "review the plan", "review the design", "review architecture"
  • Investigate Mode: The task needs reach a hermetic sandbox denies — it requires ANY of: project credentials, network access, external systems (DB / cloud / API), live data, or non-hermetic execution. Detected by capability-need, not by guessing intent — e.g. "have Codex dig into the data", "give Codex DB access to find the cause", "let Codex actually run X against the live system". Check this BEFORE falling through to General.
  • General Mode: Everything else (give opinion, analyze code, brainstorm, ask a question) — stays hermetic (read-only, no network)

Finding Triage — before you adopt Codex's findings

Codex biases toward robustness and edge cases. Before treating any Codex finding as must-fix (P0/P1/P2) and opening a revision-loop round (.claude/rules/workflow.md Revision Loop Protocol), apply this filter. It governs how severity gets assigned — once assigned, the loop protocol is unchanged: P0/P1/P2 still must be fixed before proceeding.

Read the full file on GitHub · 392 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 392 lines · 0 tokens per session scan A 96c711385bbe

Subscribe to this mod's changes

codex is a command published in the GitHub repository pablomarin/claude-codex-forge (5 stars, last pushed 4d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 7,478 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.