agent-skills: Instructions file for Codex

AGENTS.md

agent-skills AGENTS.md is an instructions file for Codex, OpenCode from motherduckdb/agent-skills. It costs 2,005 tokens per session, scanned A, original, no licence file.

Repository-specific instructions stored in an AGENTS.md file for the motherduckdb/agent-skills project.

In plain words
What is it for?
For making changes in that repository while preserving its required conventions and product settings.
Why use it?
It tells coding agents which project structure, content rules, defaults, and editing practices to follow.

Instructions file for CodexOpenCode

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

This is motherduckdb/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 motherduckdb/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/motherduckdb/agent-skills/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/motherduckdb/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/motherduckdb/agent-skills/agents-md/github.svg)](https://agentmods.dev/instructions/motherduckdb/agent-skills/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/motherduckdb/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/motherduckdb/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/motherduckdb/agent-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/motherduckdb/agent-skills/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,005 This file is loaded in full into every session.
When invoked 2,005 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 $0.02005 $0.02005
Opus 5.5 $0.00802 $0.00802
Sonnet 5.5 $0.00401 $0.00401
Haiku 4.5 $0.00200 $0.00200

Measured 2d ago against content hash fc6328df7421, 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 2d 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 · 157 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

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. 2d ago Changed · +7 lines · +112 tokens per session fc6328df7421
  2. 1mo ago Changed · +10 tokens per session 21c96a193b8d
  3. 1mo ago Changed · +2 lines · +52 tokens per session 4e7f9bd725f8
  4. 1mo ago First seen · 148 lines · 1,831 tokens per session scan A 60e1dc967f6d

Subscribe to this mod's changes

agent-skills AGENTS.md is an instructions file published in the GitHub repository motherduckdb/agent-skills (62 stars, last pushed 2d ago), with no licence file. It adds 2,005 tokens to every session, about $0.0080 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

Other instructions, from other repositories