etyb-skills: Instructions file for Codex

AGENTS.md

etyb-skills AGENTS.md is an instructions file for Codex, OpenCode from e-t-y-b/etyb-skills. It costs 757 tokens per session, scanned A, original, MIT.

A single engineering skill called ETYB that acts as a software team by routing work to specialist roles inside one agent workflow.

In plain words
What is it for?
Use it with /etyb or automatically during software work to guide decisions, choose an appropriate level of process, and consult its stored vendor guidance.
Why use it?
It helps apply consistent engineering practices across coding, architecture, debugging, testing, security, and other software tasks.

Instructions file for CodexOpenCode

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

This is e-t-y-b/etyb-skills's own configuration. It tells Codex and OpenCode how to work on etyb-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 etyb-skills configures →

Reuse

Borrowing it

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

Made for: Codex, OpenCode.

Wrote this? Show the measurements

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Per session 757 This file is loaded in full into every session.
When invoked 757 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 $0.00757 $0.00757
Opus 5 $0.00378 $0.00378
Sonnet 5 $0.00151 $0.00151
Haiku 4.5 $0.00076 $0.00076

Measured 10d ago against content hash 5dc7aa150535, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

etyb-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 10d 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 · 60 lines

How it starts

The opening of the file, as written. The whole thing — 60 lines — stays where its author put it; the contents beside it link to each section on GitHub.

etyb-skills

ETYB is an engineering co-pilot packaged as a single agent skill (/etyb). It acts as a senior engineering leader for any software situation — code, architecture, debugging, review, infra, testing, security, performance — by routing internally to specialist roles, enforcing engineering discipline, and reading currency-stamped vendor knowledge from disk. Users never invoke a specialist directly; everything routes through the one skill.

Invocation

Invoke explicitly with /etyb, or let it auto-trigger: the skill's description matches engineering situations (a bug, an architecture question, an X-vs-Y tradeoff, a platform name in conversation), so agents load it whenever the request has software content.

Tier model

  • Tier 0 — trivial: just do it, no ceremony.
  • Tier 1 — single-domain: act as one specialist, read that one reference.
  • Tier 2 — incident: skip ceremony, triage immediately.
  • Tier 3-4 — multi-domain or high-stakes: written plan plus gate sequence.

Repo layout

  • skills/etyb/ — the skill itself; SKILL.md is the only trigger surface.
  • skills/etyb/core/ — orchestration modules (tiering, gates, routing, knowledge currency).
  • skills/etyb/references/specialists/ — specialist role references (time-invariant principles).
  • skills/etyb/references/protocols/ — always-on engineering protocols.
  • skills/etyb/references/verticals/ — business-domain architect references.
  • stacks/<vendor>/ — currency-stamped vendor pages; detection via each stack's SKILL.md, depth from sibling product/role pages with last_verified_on stamps.
  • docs/plan/ — execution plans; docs/ — RFCs and architecture docs.

Conventions

  • TDD — no production code without a failing test first.
  • Verification before claims — evidence, not assertion; verify each step before advancing.
  • At most 3 clarifying questions, and only when the answer changes the work.
  • Signature footer — every Tier 1-4 response ends with the ETYB signature block.

Read the full file on GitHub · 60 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. 10d ago First seen · 60 lines · 757 tokens per session scan A 5dc7aa150535

Subscribe to this mod's changes

etyb-skills AGENTS.md is an instructions file published in the GitHub repository e-t-y-b/etyb-skills (10 stars, last pushed 2mo ago), licensed MIT. It adds 757 tokens to every session, about $0.0038 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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