agent-skills: Instructions file for Codex

AGENTS.md

agent-skills AGENTS.md is an instructions file for Codex, OpenCode from Codagent-AI/agent-skills. It costs 116 tokens per session, scanned A, original, MIT.

Development notes for creating agent skills and their frontmatter, which is the metadata block at the top of a skill file. It explains a naming rule needed for correct namespaced display.

In plain words
What is it for?
Use it when creating or reviewing skill metadata, especially when the skill should appear with its repository namespace.
Why use it?
It prevents a frontmatter setting from replacing the intended skill name with an incorrect or generic label.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: reads .claude/ paths.

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

Reuse

Borrowing it

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

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/codagent-ai/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/codagent-ai/agent-skills/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 116 This file is loaded in full into every session.
When invoked 116 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 $0.00116 $0.00116
Opus 5.5 $0.00046 $0.00046
Sonnet 5.5 $0.00023 $0.00023
Haiku 4.5 $0.00012 $0.00012

Measured 1mo ago against content hash 9dddf0bc1a86, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

agent-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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

AGENTS.md · 10 lines

What it actually says

Agent Skills — Development Notes

Skill frontmatter

Do NOT add a name field to skill frontmatter. The name field overrides the skill's display prefix, causing it to show an incorrect or generic name instead of the proper namespaced prefix (e.g. codagent:handoff).

Releases

Every PR must include a release. Run the release skill (.claude/skills/release) before creating or pushing a PR so the branch carries the version bump and changelog entry. Do not open a PR without it.

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 · +4 lines · +51 tokens per session 9dddf0bc1a86
  2. 2mo ago First seen · 6 lines · 65 tokens per session scan A 9b76e1846233

Subscribe to this mod's changes

agent-skills AGENTS.md is an instructions file published in the GitHub repository Codagent-AI/agent-skills (31 stars, last pushed 11d ago), licensed MIT. It adds 116 tokens to every session, about $0.0005 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.

Related

agent-skills AGENTS.md compared with instructions from other repositories

agent-skills AGENTS.md next to 6 instructions from other repositories
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agent-skills AGENTS.mdCodagent-AI/agent-skillsInstructions file3111d agoMITA116Codex, OpenCode
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next.js AGENTS.mdvercel/next.jsInstructions file143kyesterdayMITA7,461Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchainInstructions file149kyesterdayMITA4,680Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA5,516GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA3,093GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harnessInstructions file274k2d agoMITA4,313Codex, OpenCode