demo

demo is a command for Claude Code, Codex from hamza-ali-shahjahan/claudex. It costs 22 tokens per session (1,019 once invoked), scanned C, a copy of demo, MIT.

A short, isolated coding demonstration in which Claude and Codex independently review deliberately buggy code. It uses a temporary Git repository so the user's files are not changed.

In plain words
What is it for?
Use it as a first-time demo of collaborative code review, provided Codex is installed and authenticated.
Why use it?
It provides a safe way to see how a two-agent code review works and compare which bugs each reviewer finds.

Command for Claude CodeCodex

Written for Claude Code and Codex: shipped in a Claude Code plugin, but also runs codex exec. Also seen: mentions Codex.

Part of the claudex plugin — 1 skill, 7 commands, 1 hook shipped together

Good fit Use it as a first-time demo of collaborative code review, provided Codex is installed and authenticated.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/hamza-ali-shahjahan/claudex/demo
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.

Clone the repo
git clone --depth 1 https://github.com/hamza-ali-shahjahan/claudex

Made for: Claude Code, Codex.

Or install claudex, the plugin that ships this one along with the rest of its 1 skill, 7 commands, 1 hook.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for demo

README.md
[![agentmods](https://agentmods.dev/badge/commands/hamza-ali-shahjahan/claudex/demo/github.svg)](https://agentmods.dev/commands/hamza-ali-shahjahan/claudex/demo)
Your own site
<a href="https://agentmods.dev/commands/hamza-ali-shahjahan/claudex/demo"><img src="https://agentmods.dev/badge/commands/hamza-ali-shahjahan/claudex/demo/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for demo

Your own site · 80×15
<a href="https://agentmods.dev/commands/hamza-ali-shahjahan/claudex/demo"><img src="https://agentmods.dev/badge/commands/hamza-ali-shahjahan/claudex/demo.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 22 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,019 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod 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 5.1 $0.00022 $0.01019
Opus 5 $0.00011 $0.00509
Sonnet 5 $0.00004 $0.00204
Haiku 4.5 $0.00002 $0.00102

Measured 11d ago against content hash 3a04bf1c1930, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade C, and why

demo scanned grade C with 1 finding 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 11d 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.

Recursive force deletehighDestructive command

rm -rf with a variable or a broad path is one typo away from removing the wrong tree.

8. **Clean up.** Remove the throwaway directory (`rm -rf "$DEMO"` — it is a
Origin

This is a copy

100% identical to demo — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/claudex/commands/demo.md · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are running the ClauDex demo — a safe, self-contained first experience of the duet. You will plant bugs, let both models review them independently, and reveal who caught what. Everything happens in a throwaway directory; the user's own files are never touched.

Sign-off contract: this is a real review, so the normal rules apply — end with reviewed with love by ClauDex 🧡🖤 ONLY if Codex successfully delivered its review; if the Codex call fails (after one retry), end unsigned with the interruption message.

Preflight — it takes two to ClauDex

Run codex --version and check auth (codex login status or equivalent). If either fails, STOP and reply with exactly:

It takes two to ClauDex. 🧡 Claude is here — 🖤 Codex is not, so there is no duet to demo. Fix it in two lines, then come back:

npm i -g @openai/codex
codex login

(No git preflight — the demo brings its own repo.)

The demo

  1. Set the stage. Create a throwaway workspace and repo: DEMO=$(mktemp -d "${TMPDIR:-/tmp}/claudex-demo.XXXXXX") && git -C "$DEMO" init -q

  2. Plant the bugs. Write exactly this to $DEMO/discount.js:

    // discount.js — apply coupon discounts to a shopping cart
    function applyDiscount(cart, coupon) {
      let total = 0;
      for (let i = 0; i <= cart.length; i++) {
        total += cart[i].price * cart[i].qty;
      }
    
      if (coupon.type == "percent") {
        total = total - (total * coupon.value) / 100;
      } else {
        total = total - coupon.value;
      }
    
      cart.forEach((item) => (item.discounted = true));
    
      return "$" + total.toFixed(2);
    }
    
    module.exports = { applyDiscount };
    

    For your own reveal later, the planted issues are: (a) off-by-one i <= cart.length — guaranteed crash; (b) no validation of coupon.value — negative totals, >100% discounts; (c) loose == comparison; (d) the function silently mutates the caller's cart; (e) floating-point money math. Do NOT tell either reviewer this list.

  3. Tell the user what's happening in two sentences: bugs are planted — some obvious, some subtle, one a pure judgment call — and the two models will now review the same file independently.

  4. Claude's review (yours). Review discount.js and write down your findings BEFORE consulting Codex.

  5. Codex's review. With a hard timeout of ~10 minutes:

Read the full file on GitHub · 93 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. 11d ago First seen · 93 lines · 22 tokens per session scan C 3a04bf1c1930

Subscribe to this mod's changes

demo is a command published in the GitHub repository hamza-ali-shahjahan/claudex (4 stars, last pushed 1mo ago), licensed MIT. It adds 22 tokens to every session and 1,019 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it C with 1 finding (recursive force delete). It is 100% identical to demo, differing in 0 lines, and is treated as a copy.