agentrules-architect: Instructions file for Codex

AGENTS.md

agentrules-architect AGENTS.md is an instructions file for Codex, OpenCode from trevor-nichols/agentrules-architect. It costs 4,520 tokens per session, scanned A, original, MIT.

A set of instructions for developing and maintaining the AgentRules Architect codebase, including its project structure, work plans, milestones, and engineering principles.

In plain words
What is it for?
Use it when working on that repository to guide code changes, tests, continuous-integration files, command-line workflows, and type definitions.
Why use it?
It gives coding agents consistent rules for making focused, testable, and maintainable changes.

Instructions file for CodexOpenCode

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

This is trevor-nichols/agentrules-architect's own configuration. It tells Codex and OpenCode how to work on agentrules-architect 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 agentrules-architect configures →

Reuse

Borrowing it

Nothing to install: this file belongs to trevor-nichols/agentrules-architect. 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/trevor-nichols/agentrules-architect/main/AGENTS.md
Clone the repo
git clone --depth 1 https://github.com/trevor-nichols/agentrules-architect

Made for: Codex, OpenCode.

Wrote this? Show the measurements

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README.md
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Per session 4,520 This file is loaded in full into every session.
When invoked 4,520 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 5.1 $0.04520 $0.04520
Opus 5 $0.02260 $0.02260
Sonnet 5 $0.00904 $0.00904
Haiku 4.5 $0.00452 $0.00452

Measured 6d ago against content hash a6dc92ddc92f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

agentrules-architect 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 6d 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 · 373 lines

How it starts

The opening of the file, as written. The whole thing — 373 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are an expert senior software engineer and AI coding agent assigned to maintain and evolve the AgentRules Architect codebase (the repository with root package src/agentrules). Your remit is to produce high-quality, maintainable, and auditable code changes, tests, and CI artifacts that remediate the high-impact issues described in the attached project report and follow the repository layout and conventions in the provided project structure.

Development Principles

  • DRY — remove duplication, centralize shared logic (especially provider coercion and token logic).
  • KISS — prefer simple, well-tested solutions over speculative complexity.
  • YAGNI — do not add features that aren’t strictly required to fix the problem at hand.
  • Single Responsibility — each module/class/function should do one thing well.
  • Fail-fast & explicit errors — surface errors early with actionable messages.
  • Prioritize long-term maintainability and auditability.
  • Use type annotations and keep stubs (.pyi) in sync with implementation.
  • When unsure about the best approach, gather more data (run tests, reproduce locally, add lightweight probes) rather than guessing.
  • Keep this AGENTS.md file up-to-date and update/edit for any significant changes.
  • Throughout the codebase you will see SNAPSHOT.md files. These files contain architectural documentation using directory trees with inline comments. Refer to them to understand and navigate the project efficiently. When files are added/removed/moved, update SNAPSHOT.md fils by running agentrules snapshot sync (preserves comments, but does not add comments).

ExecPlans

  • When writing complex features or refactors, use an ExecPlan (as described in .agent/PLANS.md) from design to implementation.

Milestones

  • When the feature or refactor your writing is significantly complex, disaggregate the ExecPlan into milestones (as described in .agent/templates/MILESTONE_TEMPLATE.md)

Prefer CLI creation over manual file creation:

  • ExecPlan:
    • Create: agentrules execplan new "<title>" --slug <short-slug>
    • Complete: agentrules execplan complete EP-YYYYMMDD-NNN
  • Milestones:
    • Create: agentrules execplan milestone new EP-YYYYMMDD-NNN "<Milestone Title>" [--ms <N>]
    • Complete: agentrules execplan milestone complete EP-YYYYMMDD-NNN --ms <N>

Read the full file on GitHub · 373 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. 6d ago First seen · 373 lines · 4,520 tokens per session scan A a6dc92ddc92f

Subscribe to this mod's changes

agentrules-architect AGENTS.md is an instructions file published in the GitHub repository trevor-nichols/agentrules-architect (122 stars, last pushed 7d ago), licensed MIT. It adds 4,520 tokens to every session, about $0.0226 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 2026-08-30.

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