agent-skills: Instructions file for Claude Code

AGENTS.md

agent-skills AGENTS.md is an instructions file for Claude Code, Codex, OpenCode from a-tokyo/agent-skills. It costs 1,125 tokens per session, scanned A, original, MIT.

Repository instructions for agent-skills, a monorepo containing many reusable skills for AI coding assistants.

In plain words
What is it for?
Use them when adding, testing, documenting, or packaging a skill for agents such as Cursor, Claude Code, Codex, or other supported tools.
Why use it?
They explain that a monorepo holds multiple related packages and show where skills, benchmarks, documentation, and marketplace entries belong.

Instructions file for Claude CodeCodexOpenCode

Written for Claude Code and Codex and OpenCode: Claude Code plugin machinery, but also the file is AGENTS.md. Also seen: mentions Claude Code; mentions AGENTS.md; mentions Codex.

This is a-tokyo/agent-skills's own configuration. It tells Claude Code, 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 a-tokyo/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/a-tokyo/agent-skills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/a-tokyo/agent-skills

Made for: Claude Code, 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/a-tokyo/agent-skills/agents-md.svg)](https://agentmods.dev/instructions/a-tokyo/agent-skills/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/a-tokyo/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/a-tokyo/agent-skills/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,125 This file is loaded in full into every session.
When invoked 1,125 The same file — it is already loaded in full.
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 5.1 $0.01125 $0.01125
Opus 5 $0.00562 $0.00562
Sonnet 5 $0.00225 $0.00225
Haiku 4.5 $0.00112 $0.00112

Measured 6d ago against content hash 69998be828c3, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, 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 6d 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 · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

AGENTS.md

Contributor and agent contract for agent-skills. Follows the agents.md format. For the user-facing skill catalogue, see README.md.

Project Overview

A monorepo of reusable agent skills (a SKILL.md plus optional references) for AI coding assistants, installed via npx skills and compatible with Cursor, Claude Code, Codex, and 40+ agents. Each skill is self-contained and ships on its own. There is no application to build or server to run — the "product" is the skill files; the "tests" are benchmarks.

Repo structure (monorepo)

skills/<name>/                     a shippable skill: SKILL.md (+ optional references/, README.md)
benchmarks/<name>/                 benchmark for that skill — OUTSIDE skills/ so it doesn't ship on install
docs/                              contributor guides (this contract links into them)
.claude-plugin/marketplace.json    Claude Code plugin marketplace — one entry per skill in skills/
README.md                          user-facing skill catalogue + install

The closest AGENTS.md wins; this root file governs the whole repo.

Setup & commands

# install / use a skill (consumer side)
npx skills add a-tokyo/agent-skills                      # all skills
npx skills add a-tokyo/agent-skills --skill production-grade

# check every skill against the platform limits (run from repo root)
wc -l skills/*/SKILL.md                                  # whole-file lines (guideline: keep body < 500; this count includes frontmatter)
# full name + description check (handles folded YAML): see docs/skill-authoring.md

# run a skill's benchmark (from inside the repo)
cd benchmarks/<name> && cat README.md                    # method + reproduce steps

There is no root package.json; benchmarks carry their own toolchain (Node + uv/promptfoo).

Code Style — skill authoring

Full rules and the compliance check: docs/skill-authoring.md. The source of truth is Anthropic's best-practices and API guides — the table below is a mirror, confirm at the guide.

Read the full file on GitHub · 91 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. 6d ago First seen · 91 lines · 1,125 tokens per session scan A 69998be828c3

Subscribe to this mod's changes

agent-skills AGENTS.md is an instructions file published in the GitHub repository a-tokyo/agent-skills (15 stars, last pushed 1mo ago), licensed MIT. It adds 1,125 tokens to every session, about $0.0056 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 2026-08-30.

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