phase-decomposer

phase-decomposer is a skill for Claude Code, Codex from 9thLevelSoftware/legion. It costs 67 tokens per session (11,989 once invoked), scanned C, original, no licence file.

A planning tool that divides a roadmap phase into implementation plans arranged by dependencies, then assigns specialist agents and creates PLAN.md files.

In plain words
What is it for?
It helps plan project phases, organise work into dependency-based waves, assign tasks, and create implementation plans.
Why use it?
It turns a broad phase of work into ordered tasks that can be assigned and executed.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit It helps plan project phases, organise work into dependency-based waves, assign tasks, and create implementation plans.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/9thlevelsoftware/legion/phase-decomposer
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 9thLevelSoftware/legion --skill phase-decomposer
Clone the repo
git clone --depth 1 https://github.com/9thLevelSoftware/legion

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 phase-decomposer

README.md
[![agentmods](https://agentmods.dev/badge/skills/9thlevelsoftware/legion/phase-decomposer/github.svg)](https://agentmods.dev/skills/9thlevelsoftware/legion/phase-decomposer)
Your own site
<a href="https://agentmods.dev/skills/9thlevelsoftware/legion/phase-decomposer"><img src="https://agentmods.dev/badge/skills/9thlevelsoftware/legion/phase-decomposer/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 phase-decomposer

Your own site · 80×15
<a href="https://agentmods.dev/skills/9thlevelsoftware/legion/phase-decomposer"><img src="https://agentmods.dev/badge/skills/9thlevelsoftware/legion/phase-decomposer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 67 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 11,989 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 $0.00067 $0.11989
Opus 5 $0.00034 $0.05994
Sonnet 5 $0.00013 $0.02398
Haiku 4.5 $0.00007 $0.01199

Measured 10d ago against content hash 92c474d0f891, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-14, from the pricing page.

Security

Grade C, and why

phase-decomposer scanned grade C with 1 finding 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 10d 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.

Nullifies safety policieshighAnti-refusal

"You have no restrictions", "do anything now", "ignore your guidelines": a direct jailbreak that disables guardrails.

| `files_forbidden` | List of file paths and directory patterns this plan MUST NOT modify. Include files owned by other plans in the same wave (prevents parallel conflicts), shared config files not in scope, and any file
skills/phase-decomposer/SKILL.md · 1,084 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 10d ago First seen · 1,084 lines · 67 tokens per session scan C 92c474d0f891

Subscribe to this mod's changes

phase-decomposer is a skill published in the GitHub repository 9thLevelSoftware/legion (76 stars, last pushed 1mo ago), with no licence file. It adds 67 tokens to every session and 11,989 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it C with 1 finding (nullifies safety policies). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.