ecma-rs: Instructions file for Codex

AGENTS.md

ecma-rs AGENTS.md is an instructions file for Codex, OpenCode from wilsonzlin/ecma-rs. It costs 8,459 tokens per session, scanned A, original, no licence file.

Repository instructions for ecma-rs, covering design principles, the intended architecture, workspace layout, integration boundaries, and modernization guidance.

In plain words
What is it for?
Use them when making changes in the ecma-rs repository, especially changes involving its architecture, workspace, or modernization.
Why use it?
They give coding agents project-specific rules and context that are not part of the source code itself.

Instructions file for CodexOpenCode

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

This is wilsonzlin/ecma-rs's own configuration. It tells Codex and OpenCode how to work on ecma-rs 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 ecma-rs configures →

Reuse

Borrowing it

Nothing to install: this file belongs to wilsonzlin/ecma-rs. 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/wilsonzlin/ecma-rs/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/wilsonzlin/ecma-rs

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 ecma-rs AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/wilsonzlin/ecma-rs/agents-md/github.svg)](https://agentmods.dev/instructions/wilsonzlin/ecma-rs/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/wilsonzlin/ecma-rs/agents-md"><img src="https://agentmods.dev/badge/instructions/wilsonzlin/ecma-rs/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 ecma-rs AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/wilsonzlin/ecma-rs/agents-md"><img src="https://agentmods.dev/badge/instructions/wilsonzlin/ecma-rs/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 8,459 This file is loaded in full into every session.
When invoked 8,459 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 $0.08459 $0.08459
Opus 5.5 $0.03384 $0.03384
Sonnet 5.5 $0.01692 $0.01692
Haiku 4.5 $0.00846 $0.00846

Measured 2mo ago against content hash fa375c9aad2d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

ecma-rs 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 2mo 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 · 829 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. 2mo ago First seen · 829 lines · 8,459 tokens per session scan A fa375c9aad2d

Subscribe to this mod's changes

ecma-rs AGENTS.md is an instructions file published in the GitHub repository wilsonzlin/ecma-rs (9 stars, last pushed 15d ago), with no licence file. It adds 8,459 tokens to every session, about $0.0338 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

ecma-rs AGENTS.md compared with instructions from other repositories

ecma-rs AGENTS.md next to 6 instructions from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
ecma-rs AGENTS.mdwilsonzlin/ecma-rsInstructions file915d agononeA8,459Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA9,719GitHub Copilot
next.js AGENTS.mdvercel/next.jsInstructions file143kyesterdayMITA7,461Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchainInstructions file149kyesterdayMITA4,680Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA5,516GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscodeInstructions file195kyesterdayMITA3,093GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harnessInstructions file274k2d agoMITA4,313Codex, OpenCode