audit-skills: Instructions file for Codex

AGENTS.md

audit-skills AGENTS.md is an instructions file for Codex, OpenCode from danygiguere/audit-skills. It costs 2,548 tokens per session, scanned A, original, MIT.

Engineering audit rules for reviewing or generating code, covering security, access control, authentication, tokens, resource ownership, data exposure, and other correctness concerns. Detailed checklists are stored in a separate audit skill.

In plain words
What is it for?
Use it when auditing, reviewing, or generating code. It guides checks for authorization, sessions, credentials, signed requests, object ownership, responses, errors, logs, APIs, dependencies, and correctness.
Why use it?
It gives every code review a baseline set of safety checks, including verifying permissions where sensitive actions happen and preventing one user from accessing another user's data.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md.

This is danygiguere/audit-skills's own configuration. It tells Codex and OpenCode how to work on audit-skills itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything audit-skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to danygiguere/audit-skills. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/danygiguere/audit-skills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/danygiguere/audit-skills

Made for: Codex, OpenCode.

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 audit-skills AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/danygiguere/audit-skills/agents-md/github.svg)](https://agentmods.dev/instructions/danygiguere/audit-skills/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/danygiguere/audit-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/danygiguere/audit-skills/agents-md/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 audit-skills AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/danygiguere/audit-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/danygiguere/audit-skills/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,548 This file is loaded in full into every session.
When invoked 2,548 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.02548 $0.02548
Opus 5 $0.01274 $0.01274
Sonnet 5 $0.00510 $0.00510
Haiku 4.5 $0.00255 $0.00255

Measured 9d ago against content hash 85fd530babf5, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

audit-skills AGENTS.md 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 9d 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.

AGENTS.md · 150 lines

How it starts

The opening of the file, as written. The whole thing — 150 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Engineering audit digest

Apply the invariants below to all code you review, audit, or generate. Detailed per-topic checklists live in the installed audit skill under references/ — by default .agents/skills/audit/references/. Read the matching file (map at the bottom) before doing an in-depth audit.

Invariants (always apply)

Access & data security

  • Authorization — every state-changing or sensitive action is permission-checked server-side at the point of action, not only in the UI or routing layer.
  • Authentication & sessions — sessions are regenerated on login and invalidated on logout; credential and reset flows do not reveal whether an account exists.
  • Token & webhook validation — stateless credentials (JWTs, API keys, signed URLs, webhook signatures) are cryptographically verified before any claim is trusted: algorithm pinned, exp/aud/iss validated, webhook HMACs computed over the raw body within a bounded timestamp window.
  • IDOR — any resource looked up by an identifier from the request is verified as owned by or visible to the current principal; a valid ID is not authorization.
  • Data exposure — responses, errors, and logs contain only fields explicitly intended for the consumer; never whole models, stack traces, or PII by default.
  • Crypto & data protection — passwords use adaptive hashing; tokens come from a CSPRNG; secret comparisons are constant-time; no homemade crypto.
  • Output encoding — every user-controlled value rendered into HTML, JS, CSS, URLs, headers, or emails is encoded for that exact context.
  • Tenant isolation — in multi-tenant code, every query, cache key, and background job is scoped by tenant; no implicit global reads.
  • CSRF — state-changing endpoints authenticated by cookies verify a CSRF token or origin (not applicable to pure token-based APIs).
  • Mass assignment — request data is never bound wholesale onto models; every binding site has an explicit, per-context allowlist of writable fields (allowlists, never denylists).

Read the full file on GitHub · 150 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. 9d ago First seen · 150 lines · 2,548 tokens per session scan A 85fd530babf5

Subscribe to this mod's changes

audit-skills AGENTS.md is an instructions file published in the GitHub repository danygiguere/audit-skills (5 stars, last pushed 2mo ago), licensed MIT. It adds 2,548 tokens to every session, about $0.0127 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 instructions, from other repositories

next.js AGENTS.md

AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.

vercel/next.js · 7,296 tokens

codex AGENTS.md

AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.

openai/codex · 5,153 tokens

vscode buildNext.instructions.md

Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).

microsoft/vscode · 6,785 tokens

vscode oss-third-party-notices.instructions.md

Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).

microsoft/vscode · 5,001 tokens

langchain AGENTS.md

AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.

langchain-ai/langchain · 4,469 tokens

deepseek-harness AGENTS.md

AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.

deepseek-ai/deepseek-harness · 3,735 tokens