codex-reality-rules AGENTS.md

codex-reality-rules AGENTS.md is an instructions file for Codex, OpenCode from gencmedya/codex-reality-rules. It costs 1,088 tokens per session, scanned A, original, MIT.

Repository-wide instructions for an AI coding agent. They set rules such as understanding the code before editing, making focused changes, and working toward results that can be checked.

In plain words
What is it for?
Guiding code changes, checking the working tree, identifying assumptions, and deciding how much planning and testing a task needs.
Why use it?
They reduce accidental changes and encourage evidence-based edits that are easier to review and verify.

Instructions file for CodexOpenCode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/gencmedya/codex-reality-rules/agents-md
Clone the repo
git clone --depth 1 https://github.com/gencmedya/codex-reality-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 codex-reality-rules AGENTS.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/gencmedya/codex-reality-rules/agents-md.svg)](https://agentmods.dev/instructions/gencmedya/codex-reality-rules/agents-md)
Your own site
<a href="https://agentmods.dev/instructions/gencmedya/codex-reality-rules/agents-md"><img src="https://agentmods.dev/badge/instructions/gencmedya/codex-reality-rules/agents-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,088 This file is loaded in full into every session.
When invoked 1,088 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.01088 $0.01088
Opus 5 $0.00544 $0.00544
Sonnet 5 $0.00218 $0.00218
Haiku 4.5 $0.00109 $0.00109

Measured 4d ago against content hash b1daccfa54c7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

codex-reality-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 4d 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 · 102 lines

How it starts

The opening of the file, as written. The whole thing — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Codex Reality Rules

Repository-wide behavioral guidance for Codex. Combine this file with accurate, project-specific architecture, build, test, and deployment instructions.

Bias toward correctness, evidence, and focused execution. Scale ceremony to risk: an obvious one-line edit does not need a long plan, while a production or multi-step change does.

1. Think Before Editing

  • Read the applicable AGENTS.md files and the relevant code, tests, configuration, and documentation before changing anything.
  • Inspect the working tree first. Treat pre-existing edits and untracked files as user-owned work; do not overwrite, revert, or reformat them incidentally.
  • Identify the requested outcome, constraints, and observable success criteria.
  • Surface assumptions that materially affect behavior, architecture, security, cost, or data. Do not silently choose between materially different interpretations.
  • Ask only when the missing answer would materially change the result or when credentials, authority, or an irreversible choice blocks real completion. Otherwise, proceed with a safe, explicit assumption.
  • Say when a simpler or safer path exists, and explain the tradeoff briefly.

2. Build the Real Thing

  • For software work, implement the real end-to-end behavior requested. Do not substitute a demo, fake backend, paper mode, simulation, placeholder feature, or hard-coded production data unless the user explicitly asks for one.
  • Mocks, fixtures, and synthetic data belong in tests only; they must not replace the production architecture or user path.
  • Every user-visible action must be wired to its real behavior, including persistence, network calls, state changes, permissions, and failure states where applicable. If the real behavior is blocked, state that clearly instead of making the interface appear functional.
  • Prefer low-cost, portable solutions that still satisfy the real requirement. Never reduce cost by quietly replacing a real system with a fake one.
  • Do not adopt a materially different architecture from the one requested without explicit approval.
  • Include necessary input validation, boundary handling, security controls, and recoverable failure behavior. Avoid speculative handling for impossible cases.

Read the full file on GitHub · 102 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. 4d ago First seen · 102 lines · 1,088 tokens per session scan A b1daccfa54c7

Subscribe to this mod's changes

codex-reality-rules AGENTS.md is an instructions file published in the GitHub repository gencmedya/codex-reality-rules (2 stars, last pushed 10d ago), licensed MIT. It adds 1,088 tokens to every session, about $0.0054 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 2026-08-31.

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