skills: Instructions file for Codex

AGENTS.md

skills AGENTS.md is an instructions file for Codex, OpenCode from trailofbits/skills. It costs 4,947 tokens per session, scanned A, original, CC-BY-SA-4.0.

Instructions for contributing to the Trail of Bits skills repository, including its resources, technical references, Codex compatibility, and plugin structure.

In plain words
What is it for?
Use it when developing, reviewing, or contributing skills to the Trail of Bits skills repository. It covers the relevant documentation and plugin files.
Why use it?
It explains the repository's contribution rules and expected organization. This helps contributors make changes that fit the project's conventions.

Instructions file for CodexOpenCode

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

This is trailofbits/skills's own configuration. It tells Codex and OpenCode how to work on 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 skills configures →

About the project

Trail of Bits Skills Marketplace is a collection of Claude Code plugins, skills, agents, commands, and instructions for security analysis, vulnerability detection, code auditing, and development workflows. It is for developers and security researchers using AI-assisted tools to inspect software, smart contracts, CI workflows, and related artifacts. The catalogue entries are examples of the marketplace’s reusable agent extensions.

trailofbits/skills · 7,824 stars · on GitHub

Reuse

Borrowing it

Nothing to install: this file belongs to trailofbits/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/trailofbits/skills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/trailofbits/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 skills AGENTS.md

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/trailofbits/skills/agents-md"><img src="https://agentmods.dev/badge/instructions/trailofbits/skills/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 4,947 This file is loaded in full into every session.
When invoked 4,947 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 unknown 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 $0.04947 $0.04947
Opus 5.5 $0.01979 $0.01979
Sonnet 5.5 $0.00989 $0.00989
Haiku 4.5 $0.00495 $0.00495

Measured 1mo ago against content hash 78f5a80f6f25, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

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 1mo 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 · 385 lines

The source is not reproduced here

Licensed CC-BY-SA-4.0

The repository is licensed CC-BY-SA-4.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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. 1mo ago Changed · -1 lines · +7 tokens per session 78f5a80f6f25
  2. 1mo ago Changed · +9 lines · +153 tokens per session 4dd9d53648a8
  3. 1mo ago Changed · +2 lines · +40 tokens per session f0fce5b2f6f1
  4. 1mo ago First seen · 375 lines · 4,747 tokens per session scan A 65a28a0971a7

Subscribe to this mod's changes

skills AGENTS.md is an instructions file published in the GitHub repository trailofbits/skills (7,824 stars, last pushed 3d ago), licensed CC-BY-SA-4.0. It adds 4,947 tokens to every session, about $0.0198 per session on Opus 5.5. 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 2026-08-30.

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