mcp-environtment-browser: Instructions file for Codex

AGENTS.md

mcp-environtment-browser AGENTS.md is an instructions file for Codex, OpenCode from yadenmustopa/mcp-environtment-browser. It costs 2,683 tokens per session, scanned B, original, MIT.

Repository instructions for an agent working on a browser-environment project. They document the owner’s fixed decisions and require the simplest approach that meets the goal.

In plain words
What is it for?
Use them as guardrails before changing the project, especially around browser tabs, local credentials, Playwright, licensing, and distribution.
Why use it?
They stop an agent from adding unapproved layers, changing storage or browser location, or introducing extra pricing and anti-piracy features.

Instructions file for CodexOpenCode

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

This is yadenmustopa/mcp-environtment-browser's own configuration. It tells Codex and OpenCode how to work on mcp-environtment-browser 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 mcp-environtment-browser configures →

Reuse

Borrowing it

Nothing to install: this file belongs to yadenmustopa/mcp-environtment-browser. 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/yadenmustopa/mcp-environtment-browser/master/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/yadenmustopa/mcp-environtment-browser

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.

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README.md
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Your own site
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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.

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Your own site · 80×15
<a href="https://agentmods.dev/instructions/yadenmustopa/mcp-environtment-browser/agents-md"><img src="https://agentmods.dev/badge/instructions/yadenmustopa/mcp-environtment-browser/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 2,683 This file is loaded in full into every session.
When invoked 2,683 The same file — it is already loaded in full.
Security scan B 1 finding. 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 $0.02683 $0.02683
Opus 5 $0.01341 $0.01341
Sonnet 5 $0.00537 $0.00537
Haiku 4.5 $0.00268 $0.00268

Measured 9d ago against content hash b3db1db07822, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade B, and why

mcp-environtment-browser AGENTS.md scanned grade B with 1 finding 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 9d 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.

Asks for rootmediumPrivilege escalation

A mod that escalates privileges can change anything on the machine, not only the project.

| Security-conscious | Tidak ada password via chat. Manual sudo kalau perlu. Backup sebelum destructive op. |
AGENTS.md · 225 lines

How it starts

The opening of the file, as written. The whole thing — 225 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Agent Strict Guidelines — mcp-environtment-browser

WAJIB BACA sebelum agent (atau developer) melakukan perubahan apa pun di repo ini. Dokumen ini meng-encode prinsip owner (yadenmustopa) supaya agent tidak over-engineer dan tetap di jalur paling sederhana.


🚨 The Golden Rule

Default ke opsi paling sederhana yang memenuhi goal. Jangan tambahkan fitur, layer, atau abstraksi tanpa trigger eksplisit dari owner. Jika ragu, pilih yang lebih simple — bukan yang lebih powerful.


1. Batasan Strategi (JANGAN DIUBAH TANPA DISKUSI OWNER)

❌ TIDAK BOLEH — sudah diputuskan di K1-K7

Topik Keputusan tetap Jangan
Per-tab metric browser.new_page() = 1 tab ❌ Jangan ganti ke network request / wall-clock / action event
Credential location Local (libsecret) ❌ Jangan pindah ke server tanpa trigger (lihat roadmap_migration.md §Phase 2)
Browser location Local (Playwright) ❌ Jangan host di cloud / pakai browser farm
License tier (Phase 1) Dev/free only ❌ Jangan tambah tier baru / Stripe / billing logic
Anti-piracy Binary distro + license gate ❌ Jangan tambah obfuscation / DRM / TPM di Phase 1
Counter sync Real-time per-tab ❌ Jangan ganti ke batch sync (akan weaken license gate)
Hardware-bound key TIDAK untuk Phase 1 ❌ Jangan tambah TPM2/scrypt master key di Phase 1
Stack Python + FastAPI + Click + Playwright ❌ Jangan switch ke Node.js/Go/Rust
Lisensi repo MIT ❌ Jangan ganti ke proprietary/BSL
Branch default master ❌ Jangan rename ke main
Strategi A. Local-first + license-only ❌ Jangan lompat ke Strategi D

✅ BOLEH dengan diskusi owner

  • Bug fix yang tidak改变 arsitektur
  • Deps upgrade yang aman (patch version)
  • Test coverage improvement
  • Doc clarification (no decision change)
  • Refactor internal yang tetap di Strategi A

⚠️ BUTUH PERSETUJUAN EKSPLISIT OWNER

  • Tambah MCP tool baru (cek dulu apakah smart_* yang sudah ada cukup)
  • Tambah credential type baru (Phase 1: 4 types, jangan expand tanpa trigger)
  • Tambah backend/platform support (Windows/macOS = Phase 2)
  • Tambah workflow logic baru (login flow per target)
  • Performance optimization (caching, prefetch, dll)
  • Security hardening di luar scope K1-K7

Read the full file on GitHub · 225 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. 9d ago First seen · 225 lines · 2,683 tokens per session scan B b3db1db07822

Subscribe to this mod's changes

mcp-environtment-browser AGENTS.md is an instructions file published in the GitHub repository yadenmustopa/mcp-environtment-browser (0 stars, last pushed 24d ago), licensed MIT. It adds 2,683 tokens to every session, about $0.0134 per session on Opus 5. A static security scan graded it B with 1 finding (asks for root). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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