Task Decomposition

---
title: "Task Decomposition"
description: "Split a feature or engineering task into independently shippable, verifiable subtasks with explicit dependency ordering. Use when the task is too big for a single implementation pass, when you need to parallelize work across multiple agents, or when you need confidence in a phased deliverable."
author: AgentArmory
license: Proprietary
---

# Task Decomposition

Split a feature into independently shippable, verifiable subtasks. This is the skill you load BEFORE starting Implementation Workflow, when the feature is complex enough that a single implementation pass would risk failure cascades, missing dependencies, or unbounded scope.

Research shows that AI agents working on long-horizon tasks degrade in code quality with each turn (SlopCodeBench, 2026) and that the #1 cited improvement for AI coding is "better task decomposition" (Stack Overflow, 2026). This skill is designed to contain that degradation.

## Table of Contents

- [When to Use](#when-to-use)
- [Triggers](#triggers)
- [Prerequisites](#prerequisites)
- [Methodology](#methodology)
- [Dos](#don'ts)
- [Dos](#dos)
- [Pitfalls](#pitfalls)
- [Nonsense Check](#nonsense-check)
- [Validate Before Shipping](#validate-before-shipping)
- [Cross-Skill Hints](#cross-skill-hints)

## When to Use

Use when:
- The task will require more than ~15 minutes of agent execution time (a single session)
- The feature touches multiple files, components, APIs, or databases
- You need to parallelize work across multiple agents
- The task is too large to verify in one pass
- You are planning a multi-PR feature and need a release sequence
- The user asks "what needs to happen first?"

Do NOT use for: a single function or simple change (use Implementation Workflow directly), debugging (use Systematic Debugging), or a question / research task.

## Triggers

"break this down", "subtasks", "decompose", "split into", "what are the steps", "parallelize", "phases", "milestones", "what's the order", "dependency ordering", "cut this into pieces", "chunk this"

## Prerequisites

- A clear understanding of the feature goal (acceptance criteria, spec, or ticket)
- Knowledge of the codebase structure and key files (if code-level decomposition is needed)
- The project's deployment / release cadence (affects what constitutes a shippable unit)
- Implementation Workflow skill loaded (this is a planning prelude to it)

## Methodology