ai-engineering-skills: Instructions file for Codex

AGENTS.md

ai-engineering-skills AGENTS.md is an instructions file for Codex, OpenCode from tmusser/ai-engineering-skills. It costs 385 tokens per session, scanned A, original, MIT.

Repository instructions for a collection of AI-engineering skills, with rules for loading only relevant guidance and keeping changes small and self-contained.

In plain words
What is it for?
Use them when selecting skills, changing Markdown or Python process files, and running the repository's validation checks.
Why use it?
They reduce unnecessary context, duplicated instructions, and avoidable complexity when editing the repository.

Instructions file for CodexOpenCode

Written for Codex and OpenCode: the file is AGENTS.md. Also seen: mentions Claude Code; mentions Codex.

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

Reuse

Borrowing it

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

README.md
[![agentmods](https://agentmods.dev/badge/instructions/tmusser/ai-engineering-skills/agents-md.svg)](https://agentmods.dev/instructions/tmusser/ai-engineering-skills/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/tmusser/ai-engineering-skills/agents-md"><img src="https://agentmods.dev/badge/instructions/tmusser/ai-engineering-skills/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 385 This file is loaded in full into every session.
When invoked 385 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 $0.00385 $0.00385
Opus 5 $0.00192 $0.00192
Sonnet 5 $0.00077 $0.00077
Haiku 4.5 $0.00038 $0.00038

Measured 6d ago against content hash 7352f1b049c7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

ai-engineering-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 · 71 lines

What it actually says

Agent Instructions

This repo is mostly Markdown process artifacts plus small standard-library Python scripts.

Preserve concise, actionable wording.

Do not add unnecessary framework complexity.

Do not copy from external skill repos.

Keep each skill self-contained.

When editing a skill, update related templates if needed.

Route-first context loading

Resolve the task route before loading workflow guidance.

  • Load only the selected skills and directly relevant current-state or project files by default.
  • Do not preload the full skill pack merely because it is installed.
  • Expand context when the task spans routes, a compatibility seam requires it, or verification exposes missing context.
  • Searches and reads remain allowed unless explicitly forbidden. This rule limits the default working set, not discovery.
  • Treat current project state as more authoritative than templates and examples.

See docs/context-isolation.md for the full loading and expansion rules.

Run validation after changes:

python -m py_compile scripts/validate_repo.py
python -m py_compile scripts/install_claude_code.py
python scripts/validate_repo.py

Prefer small diffs.

Preserve the MIT license and acknowledgments.

Do not add generated marketing fluff.

When editing handoff behavior, preserve Workflow state: active modes, current phase, current loop, next gate, context risk, and active hypothesis. Do not expand handoff into a transcript summary.

Quality standards

Every skill must include YAML frontmatter:

  • name
  • description

Every skill must include:

  • Purpose
  • When to use
  • Inputs
  • Workflow
  • Outputs
  • Stop conditions
  • Anti-patterns

Every template must be short and directly usable.

Every example must show a concrete use case.

Every install path must remain portable across tools.

Claude Code support is first-class.

Codex support is maintained.

Manual install must remain possible because skills are plain folders with SKILL.md files.

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 · 71 lines · 385 tokens per session scan A 7352f1b049c7

Subscribe to this mod's changes

ai-engineering-skills AGENTS.md is an instructions file published in the GitHub repository tmusser/ai-engineering-skills (4 stars, last pushed 6d ago), licensed MIT. It adds 385 tokens to every session, about $0.0019 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.

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