Storybook Testing Workflow Skill for MCP Agent

Storybook Testing Workflow

A story is the cheapest reviewable proof that a component change does what the ticket says — and since Storybook 9 it can also be a real CI gate. This pack covers writing stories that function as review artefacts and wiring them into test gates, on the current major, with the package moves that silently break v8-era configuration called out explicitly.

Package facts were verified against registry.npmjs.org and the shipped @storybook/react 10.5.7 types on 2026-08-08. Storybook majors move quickly and renames land without runtime errors — re-check the version selector on any docs page before copying from it.

Module Inventory

Module	Covers	_skill.md
testing-workflow	Current-major main.ts/addon setup, theme decorators, CSF 3 stories, play interaction tests, the Vitest addon gate, the a11y ratchet, snapshot vs visual coverage	0.75

Authoring Rules

1. Name the major for every idiom. Most Storybook advice is major-specific and fails silently on the wrong one — a removed config key just stops working.
2. Shipped types over docs. Where docs and the published package disagree (exports, type parameters), the shipped .d.ts wins and the claim cites it.
3. No application-specific claims. Which major and builder a given product runs belongs in that consumer's own domain pack, never here.