Codex Explain

Codex Explain is a skill for Claude Code, Codex from dante01yoon/codex-mcp-bridge. It costs 33 tokens per session (265 once invoked), scanned A, original, MIT.

A code-explanation helper that reads specified files and returns a clear description of their purpose, logic, design choices, and non-obvious behavior.

In plain words
What is it for?
Use it when onboarding to a codebase, documenting files, reviewing an implementation, or investigating how a piece of code works.
Why use it?
It reduces the time needed to understand unfamiliar code and highlights details that may otherwise be missed.

Skill for Claude CodeCodex

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 skills/dante01yoon/codex-mcp-bridge/codex-explain
Any agent
npx skills add dante01yoon/codex-mcp-bridge --skill codex-explain
Clone the repo
git clone --depth 1 https://github.com/dante01yoon/codex-mcp-bridge

Made for: Claude Code, Codex.

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 Codex Explain

README.md
[![agentmods](https://agentmods.dev/badge/skills/dante01yoon/codex-mcp-bridge/codex-explain.svg)](https://agentmods.dev/skills/dante01yoon/codex-mcp-bridge/codex-explain)
Your own site
<a href="https://agentmods.dev/skills/dante01yoon/codex-mcp-bridge/codex-explain"><img src="https://agentmods.dev/badge/skills/dante01yoon/codex-mcp-bridge/codex-explain.svg" alt="Measured on agentmods" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 265 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 $0.00033 $0.00265
Opus 5 $0.00016 $0.00133
Sonnet 5 $0.00007 $0.00053
Haiku 4.5 $0.00003 $0.00026

Measured 4d ago against content hash 695b17224a13, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

Codex Explain 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 4d 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.

examples/claude-skills/codex-explain/SKILL.md · 28 lines

What it actually says

Explain the specified code using Codex as a sub-agent.

Steps

  1. Read the target file(s) specified in the arguments.
  2. Call mcp__codex-bridge__consult_codex_with_stdin with:
    • stdin_content: the full content of the target file(s)
    • prompt: "Explain this code clearly and concisely. Cover: 1) What it does (purpose), 2) How it works (key logic flow), 3) Important design decisions, 4) Potential gotchas or non-obvious behavior. Use plain language."
    • format: "text"
    • timeout: 180
    • sandbox: "read-only"
  3. Present the explanation. Add any additional context from the broader project if relevant.

$ARGUMENTS

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. 4d ago First seen · 28 lines · 33 tokens per session scan A 695b17224a13

Subscribe to this mod's changes

Codex Explain is a skill published in the GitHub repository dante01yoon/codex-mcp-bridge (2 stars, last pushed 6mo ago), licensed MIT. It adds 33 tokens to every session and 265 once invoked, about $0.0002 per session on Opus 5. 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.

Related

Other skills, from other repositories

hr-onboarding

A new-hire onboarding plan as a single page — first week schedule, buddy + manager intro, learning track, equipment checklist, and "you're set when…" outcomes. Use when the brief mentions "onboarding", "new hire", "first week plan", or "入职".

nexu-io/open-design · 62 tokens

book-mirror

Take any book (EPUB/PDF), produce a personalized chapter-by-chapter analysis. Each chapter is preserved in detail (The Chapter) and mirrored back to the reader's actual life (The Mirror) using brain context. The mirror observes and resonates — a friend pointing out parallels, NOT a consultant rearranging the reader's…

garrytan/gbrain · 138 tokens

miniapp

Build a tiny interactive HTML playground only when someone asks to see, play with, or step through a mechanism.

yc-software/qm · 25 tokens

eli5

Explain research, papers, or technical ideas in plain English with minimal jargon, concrete analogies, and clear takeaways. Use when the user says "ELI5 this", asks for a simple explanation of a paper or research result, wants jargon removed, or asks what something technically dense actually means.

companion-inc/feynman · 63 tokens

deck-course-module

暖纸背景 + Playfair, 左侧学习目标常驻, 含 MCQ 自测页.

nexu-io/html-anything · 25 tokens

best-practices

Searchable knowledge base of 152+ programming best practices across 30+ languages and frameworks. BM25-powered search over curated resources from industry leaders (Google, Airbnb, Uber, Mozilla, Shopify, OWASP).

dereknguyen269/programing-best-practices · 0 tokens