Borrowing it
Nothing to install: this file belongs to arcasilesgroup/ai-engineering. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/arcasilesgroup/ai-engineering/main/AGENTS.mdgit clone --depth 1 https://github.com/arcasilesgroup/ai-engineeringWrote 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.
[](https://agentmods.dev/instructions/arcasilesgroup/ai-engineering/agents-md)<a href="https://agentmods.dev/instructions/arcasilesgroup/ai-engineering/agents-md"><img src="https://agentmods.dev/badge/instructions/arcasilesgroup/ai-engineering/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.
<a href="https://agentmods.dev/instructions/arcasilesgroup/ai-engineering/agents-md"><img src="https://agentmods.dev/badge/instructions/arcasilesgroup/ai-engineering/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.01273 | $0.01273 |
| Opus 5.5 | $0.00509 | $0.00509 |
| Sonnet 5.5 | $0.00255 | $0.00255 |
| Haiku 4.5 | $0.00127 | $0.00127 |
Grade A, and why
ai-engineering 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 19d 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.
How it starts
The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md — governed by {ai} Engineering (ai-eng --version)
Guidance for AI coding agents working in this repository. Human teammates should be able to follow every line too. Only rules an agent CANNOT deduce from the code live here; if a rule becomes obvious from reading the code, delete it from this file.
Security
- Never bypass a git hook or a check: no
--no-verify, no-non commit, noHUSKY=0. - Never silence a linter: no
noqa,@ts-ignore,eslint-disable,nosec. - No secrets, no personal data, no machine-specific absolute paths in any file.
Code style
- KISS, YAGNI, DRY, SOLID, TDD, Clean Code.
- Explain it so someone who doesn't code can follow along.
- Readable code (Boswell & Foucher): minimize the time it takes someone else to understand your code.
- Names say purpose or value; no generic names (
data,temp,helperare forbidden). - Prefix booleans (
is,has,can,should); prefix limits (max,min). - Use positive conditions (
if (isValid)overif (!isInvalid)). - Early returns over deep nesting; flat control flow wins.
- Comments explain why, not what; never repeat the function signature in prose.
- Explain "huh?" moments; skip the obvious.
- One function, one job. Extract unrelated subproblems.
- Write less code: rethink requirements, use stdlib, prune unused code.
- Names say purpose or value; no generic names (
Build and test commands
typecheck: bun run typecheck (oxlint --type-aware --type-check) · lint: bun run lint (oxlint) · test: bun test · arch: bun test tests/arch.spec.ts
Workflow
- Green gate before "done": show the output of the check that proves it.
- A decision that always comes out the same is code, not a prompt.
- Task status convention (when a todo list exists): mark each task 🟢 done (paste the proving output) · 🟡 pending (name the next action) · 🔴 blocked on you (ask the exact question). No todo list → state status inline: done-with-proof, pending, or blocked.
Lifecycle
- Every skill declares its own contract — lane, artifact, successor — in a
## Lifecycleblock inside its SKILL.md: follow theNext:a skill hands you instead of asking what comes first. - The lanes are light (spike and bounded work — no contract), standard (
ai-brainstormthenai-orchestrator) and full (architectural, with the triggered nodes). - Approvals are spoken: the human says approve, ok, go or close, and you run
ai-eng spec approveorai-eng spec closeunderneath. Never ask the human to type a command; never run an approval on your own initiative.
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.
- 19d ago Changed · +9 lines · +322 tokens per session 8dadaedae6c9
- 27d ago Changed · +7 lines · +108 tokens per session ae755ac333ce
- 1mo ago Changed · +9 lines · +187 tokens per session 88b488f0be5b
- 1mo ago Changed · -6 lines · -212 tokens per session 354bdee68e5e
- 1mo ago Changed · -14 tokens per session 842f25058f3e
- 1mo ago Changed · -74 lines · -871 tokens per session a7c85217b293
- 1mo ago First seen · 122 lines · 1,753 tokens per session scan A e71c26e7014a
ai-engineering AGENTS.md is an instructions file published in the GitHub repository arcasilesgroup/ai-engineering (61 stars, last pushed 5d ago), licensed Apache-2.0. It adds 1,273 tokens to every session, about $0.0051 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.
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