omen: Instructions file for Codex

AGENTS.md

omen AGENTS.md is an instructions file for Codex, OpenCode from panbanda/omen. It costs 256 tokens per session, scanned A, original, Apache-2.0.

A repository instruction guide tells coding agents how to work in a specific Rust project. This guide says not to add Python and points agents to the project's build and test practices.

In plain words
What is it for?
Use it when an agent is changing the Omen Rust codebase, adding tests, writing command-line tools, or updating automation.
Why use it?
It keeps automated changes consistent with the project's language and rules. It also prevents helper scripts or continuous-integration steps from introducing Python where it is not wanted.

Instructions file for CodexOpenCode

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

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

Reuse

Borrowing it

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

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 omen AGENTS.md

README.md
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Your own site
<a href="https://agentmods.dev/instructions/panbanda/omen/agents-md"><img src="https://agentmods.dev/badge/instructions/panbanda/omen/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 omen AGENTS.md

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Per session 256 This file is loaded in full into every session.
When invoked 256 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 $0.00256 $0.00256
Opus 5.5 $0.00102 $0.00102
Sonnet 5.5 $0.00051 $0.00051
Haiku 4.5 $0.00026 $0.00026

Measured 29d ago against content hash d0f8791fe3d4, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

omen 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 29d 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 · 26 lines

What it actually says

AGENTS.md

Guidance for AI agents working in this repository. See CLAUDE.md for build commands, architecture, and the TDD workflow.

Do not add Python

Omen is a Rust project. Do not add Python to this repository.

This covers shipped code, helper scripts, benchmarks, evaluation harnesses, and one-off automation. Tooling that would once have been a script in scripts/ belongs in Rust instead:

  • A module under src/, exposed as a CLI subcommand (see src/eval/ and the eval command for a worked example).
  • Tests as ordinary #[cfg(test)] modules or targets under tests/, run by cargo test — not a separate interpreter invocation in CI.

If a task appears to call for a Python script, write it in Rust or ask first. Do not add a Python step to a GitHub Actions workflow.

The sole exception is parser test-fixture source: files under tests/fixtures/ that exist to be parsed by omen's tree-sitter grammars (for example tests/fixtures/sample.py). These are input data, never tooling, and are never executed.

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. 29d ago First seen · 26 lines · 256 tokens per session scan A d0f8791fe3d4

Subscribe to this mod's changes

omen AGENTS.md is an instructions file published in the GitHub repository panbanda/omen (20 stars, last pushed yesterday), licensed Apache-2.0. It adds 256 tokens to every session, about $0.0010 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 2026-09-19.

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