user-story-splitting

これはレビュー時に保存された抜粋です。完全で最新の内容は外部ソースを確認してください。

---
name: user-story-splitting
argument-hint: "[story or epic to split]"
description: Break a large story or epic into smaller deliverable stories using proven split patterns. Use when backlog items are too big for estimation, sequencing, or independent release.
intent: >-
  Break down large user stories, epics, or features into smaller, independently deliverable stories using systematic splitting patterns. Use this to make work more manageable, reduce risk, enable faster feedback cycles, and maintain flow in agile development. This skill applies to user stories, epics, and any work that's too large to complete in a single sprint.
type: component
theme: pm-artifacts
best_for:
  - "Breaking a story that's too big to estimate or finish in a sprint"
  - "Applying proven split patterns instead of splitting by component"
  - "Keeping each slice independently valuable and releasable"
scenarios:
  - "This story is too big for a sprint and splitting by frontend/backend isn't working"
  - "Our backlog items keep carrying over — I need real split patterns"
estimated_time: "15-25 min"
---


## Purpose
Break down large user stories, epics, or features into smaller, independently deliverable stories using systematic splitting patterns. Use this to make work more manageable, reduce risk, enable faster feedback cycles, and maintain flow in agile development. This skill applies to user stories, epics, and any work that's too large to complete in a single sprint.

This is not arbitrary slicing—it's strategic decomposition that preserves user value while reducing complexity.

## Input

**Works best with:** The story or epic that's too big — paste it as written.
**Also useful:** Why it's too big (can't estimate, can't finish in a sprint, can't release independently) and your team's sizing ceiling.

Anything supplied with the invocation itself — text after the skill name, a pasted context dump, or an appended `ARGUMENTS:` line — counts as answers already given. Use it and skip whatever it covers; don't re-ask.

**Arriving empty-handed? That works too.** The skill asks for the story text, then walks the split patterns against it.

**Example invocation:** `Split this: 'As an admin, I can bulk-import users from CSV, Excel, or our HR system with field mapping and error handling.'`

## Key Concepts

### The Story Splitting Framework
Based on Richard Lawrence and Peter Green's "Humanizing Work Guide to Splitting User Stories," the framework provides 8 systematic patterns for splitting work:

1. **Workflow steps:** Split along sequential steps in a user's journey
2. **Business rule variations:** Split by different rule scenarios (permissions, calculations, etc.)
3. **Data variations:** Split by different data types or inputs
4. **Acceptance criteria complexity:** Split when multiple "When" or "Then" statements exist
5. **Major effort:** Split by technical milestones or implementation phases
6. **External dependencies:** Split along dependency boundaries (APIs, third parties, etc.)
7. **DevOps steps:** Split by deployment or infrastructure requirements
8. **Tiny Acts of Discovery (TADs):** When none of the above apply, use small experiments to unpack unknowns

### Why Split Stories?
- **Faster feedback:** Smaller stories ship sooner, allowing earlier validation
- **Reduced risk:** Less to build = less that can go wrong
- **Better estimation:** Small stories are easier to estimate accurately
- **Maintain flow:** Keeps work moving through the sprint without bottlenecks
- **Testability:** Smaller scope = easier to write and run tests

### Anti-Patterns (What This Is NOT)
- **Not horizontal slicing:** Don't split into "front-end story" and "back-end story" (each story should deliver user value)
- **Not task decomposition:** Stories aren't tasks ("Set up database," "Write API")
- **Not arbitrary chopping:** Don't split "Add user management" into "Add user" and "Management" (meaningless)

### When to Use This
- Story is too large for a single sprint
- Multiple