MirrorArc: Instructions file for Codex

AGENTS.md

MirrorArc AGENTS.md is an instructions file for Codex, OpenCode from cz1993/MirrorArc. It costs 1,185 tokens per session, scanned A, original, AGPL-3.0.

Repository-specific instructions for an AI coding agent working on the MirrorArc project. The excerpt does not explain the project or list the actual ownership and data-handling rules.

In plain words
What is it for?
Use it as project context only after reading its full instructions; the supplied information does not support naming specific tasks.
Why use it?
The available description is too thin to identify the concrete guidance it provides.

Instructions file for CodexOpenCode

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

This is cz1993/MirrorArc's own configuration. It tells Codex and OpenCode how to work on MirrorArc 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 MirrorArc configures →

Reuse

Borrowing it

Nothing to install: this file belongs to cz1993/MirrorArc. 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/cz1993/MirrorArc/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/cz1993/MirrorArc

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 MirrorArc AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/cz1993/mirrorarc/agents-md/github.svg)](https://agentmods.dev/instructions/cz1993/mirrorarc/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/cz1993/mirrorarc/agents-md"><img src="https://agentmods.dev/badge/instructions/cz1993/mirrorarc/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 MirrorArc AGENTS.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/cz1993/mirrorarc/agents-md"><img src="https://agentmods.dev/badge/instructions/cz1993/mirrorarc/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 1,185 This file is loaded in full into every session.
When invoked 1,185 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 $0.01185 $0.01185
Opus 5.5 $0.00474 $0.00474
Sonnet 5.5 $0.00237 $0.00237
Haiku 4.5 $0.00119 $0.00119

Measured 1mo ago against content hash 41855f346aa5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

MirrorArc 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 1mo 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 · 85 lines

The source is not reproduced here

Licensed AGPL-3.0

The repository is licensed AGPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

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. 1mo ago Changed · +35 lines · +454 tokens per session 41855f346aa5
  2. 2mo ago First seen · 50 lines · 731 tokens per session scan A 8306e364029f

Subscribe to this mod's changes

MirrorArc AGENTS.md is an instructions file published in the GitHub repository cz1993/MirrorArc (97 stars, last pushed 1mo ago), licensed AGPL-3.0. It adds 1,185 tokens to every session, about $0.0047 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

MirrorArc AGENTS.md compared with instructions from other repositories

MirrorArc AGENTS.md next to 6 instructions from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
MirrorArc AGENTS.mdcz1993/MirrorArcInstructions file971mo agoAGPL-3.0A1,185Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscodeInstructions file195ktodayMITA9,719GitHub Copilot
next.js AGENTS.mdvercel/next.jsInstructions file143ktodayMITA7,461Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscodeInstructions file195ktodayMITA5,516GitHub Copilot
langchain AGENTS.mdlangchain-ai/langchainInstructions file149ktodayMITA4,680Codex, OpenCode
vscode copilot-instructions.mdmicrosoft/vscodeInstructions file195ktodayMITA3,093GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harnessInstructions file275k3d agoMITA4,313Codex, OpenCode