omen

omen is a skill for Claude Code, Codex from seaworld008/Commonly-used-high-value-skills. It costs 18 tokens per session (5,718 once invoked), scanned A, a copy of omen, MIT.

A pre-mortem planning tool that lists ways a plan, design, or system could fail before work begins and ranks the risks.

In plain words
What is it for?
Use it to review plans, system designs, or proposed changes for failure modes and prioritize safeguards.
Why use it?
It exposes likely problems early, when they are easier to prevent or prepare for.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents; mentions Codex.

Good fit Use it to review plans, system designs, or proposed changes for failure modes and prioritize safeguards.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/seaworld008/commonly-used-high-value-skills/omen
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.

Any agent
npx skills add seaworld008/Commonly-used-high-value-skills --skill omen
Clone the repo
git clone --depth 1 https://github.com/seaworld008/Commonly-used-high-value-skills

Made for: Claude Code, Codex.

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

README.md
[![agentmods](https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/omen/github.svg)](https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/omen)
Your own site
<a href="https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/omen"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/omen/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

Your own site · 80×15
<a href="https://agentmods.dev/skills/seaworld008/commonly-used-high-value-skills/omen"><img src="https://agentmods.dev/badge/skills/seaworld008/commonly-used-high-value-skills/omen.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,718 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 98% copy Near-identical to another mod 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 $0.00018 $0.05718
Opus 5 $0.00009 $0.02859
Sonnet 5 $0.00004 $0.01144
Haiku 4.5 $0.00002 $0.00572

Measured 4d ago against content hash febbc5ba8c48, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

omen 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.

Origin

This is a copy

98% identical to omen — 19 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

openclaw-skills/omen/SKILL.md · 314 lines

How it starts

The opening of the file, as written. The whole thing — 314 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Omen

"Foresee the fall before you leap."

A pre-mortem analysis engine. It exhaustively enumerates how a plan, design, or system will fail, in advance, and quantifies the risk. Specialized in prediction before the fact (not post-incident response — Triage) and failure-mode enumeration (not change impact — Ripple).

Principles: Failure is predictable · Optimism is the biggest risk · Warnings without quantification are ignored · Defense in depth · Assume the worst, prepare the best

Read the full file on GitHub · 314 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 Changed · -2 lines febbc5ba8c48
  2. 8d ago First seen · 316 lines · 18 tokens per session scan A 84a7e80e2e72

Subscribe to this mod's changes

omen is a skill published in the GitHub repository seaworld008/Commonly-used-high-value-skills (70 stars, last pushed 4d ago), licensed MIT. It adds 18 tokens to every session and 5,718 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 98% identical to omen, differing in 19 lines, and is treated as a copy.