cursor-rules: Instructions file for Codex

AGENTS.md

cursor-rules AGENTS.md is an instructions file for Codex, OpenCode from BOXELS/cursor-rules. It costs 290 tokens per session, scanned A, original, MIT.

A pointer file telling coding agents where a project's Cursor rules and skills are stored. These files describe project conventions such as security, structure, design, and documentation practices.

In plain words
What is it for?
Loading project rules and locating the workflow used to update documentation after a feature ships.
Why use it?
It helps agents find the instructions they must follow before changing a project, especially when they are not running inside Cursor.

Instructions file for CodexOpenCode

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

This is BOXELS/cursor-rules's own configuration. It tells Codex and OpenCode how to work on cursor-rules 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 cursor-rules configures →

Reuse

Borrowing it

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

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 cursor-rules AGENTS.md

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/boxels/cursor-rules/agents-md"><img src="https://agentmods.dev/badge/instructions/boxels/cursor-rules/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 290 This file is loaded in full into every session.
When invoked 290 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 $0.00290 $0.00290
Opus 5 $0.00145 $0.00145
Sonnet 5 $0.00058 $0.00058
Haiku 4.5 $0.00029 $0.00029

Measured today against content hash 3f484d33597f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-16, from the pricing page.

Security

Grade A, and why

cursor-rules 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 today.

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 · 19 lines

What it actually says

Agent instructions

Project conventions for AI coding agents live in .cursor/rules/*.mdc and .cursor/skills/*/SKILL.md. Cursor loads them automatically. If you are a different agent (Claude Code, Codex, Copilot, etc.), read these before making changes:

If .cursor/rules/template-repo.mdc exists, read it first — you are in the template repository, not a consumer app. That file is not part of the copy set.

  • .cursor/rules/global-rules.mdc — how to behave: ask vs. act, scope discipline, security awareness
  • .cursor/rules/product.mdc — what this is and who it's for
  • .cursor/rules/tech.mdc — stack, conventions, database, git rules
  • .cursor/rules/security.mdc — non-negotiable security rules
  • .cursor/rules/design.mdc — UI standards (only relevant when touching UI)
  • .cursor/rules/structure.mdc — where files go
  • .cursor/rules/documentation.mdc — doc location and what to keep current
  • .cursor/rules/models.mdc — Cursor-specific model guidance; safe to skip outside Cursor

Workflows: .cursor/skills/update-docs/SKILL.md (run after shipping a feature).

Don't duplicate rule content here. This file is intentionally a pointer.

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. today Changed · +2 lines · +39 tokens per session 3f484d33597f
  2. yesterday First seen · 17 lines · 251 tokens per session scan A 2663e2c4c5da

Subscribe to this mod's changes

cursor-rules AGENTS.md is an instructions file published in the GitHub repository BOXELS/cursor-rules (6 stars, last pushed yesterday), licensed MIT. It adds 290 tokens to every session, about $0.0014 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 2026-09-15.

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