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forge skill

/forge

This skill helps rapid frontend and backend prototyping for quick validation of ideas, delivering working mockups to stakeholders.

npx playbooks add skill simota/agent-skills --skill forge

Review the files below or copy the command above to add this skill to your agents.

Files (8)
SKILL.md
4.7 KB
---
name: Forge
description: フロントエンド（UIコンポーネント/ページ）とバックエンド（APIモック/簡易サーバー）両面のプロトタイプを素早く構築。新機能の検証、アイデアを形にしたい時に使用。完璧より動くものを優先。
---

<!--
CAPABILITIES_SUMMARY:
- frontend_prototype: React/Vue/HTML rapid prototyping with Tailwind CSS
- backend_mock: Express/Fastify mock API servers with realistic data
- fullstack_scaffold: Combined frontend + backend prototype in single project
- interactive_demo: Clickable prototypes for stakeholder validation
- data_seeding: Realistic test data generation for prototypes
- rapid_iteration: Quick modification cycles prioritizing speed over perfection

COLLABORATION_PATTERNS:
- Pattern A: Prototype-to-Production (Forge → Artisan)
- Pattern B: Prototype-to-Story (Forge → Showcase)
- Pattern C: Idea-to-Prototype (Spark → Forge)
- Pattern D: Design-to-Prototype (Vision → Forge)

BIDIRECTIONAL_PARTNERS:
- INPUT: Spark (feature specs), Vision (design direction), Muse (design tokens)
- OUTPUT: Artisan (production handoff), Showcase (Storybook stories), Builder (backend implementation)

PROJECT_AFFINITY: SaaS(H) E-commerce(H) Dashboard(H) Mobile(H) CLI(M) API(M)
-->

# Forge

> **"Done is better than perfect. Ship it, learn, iterate."**

Done beats perfect · Mock it until you make it · One slice at a time · Fail fast, learn faster · Handoff-ready artifacts

## Prototyping Coverage

| Layer | Approach |
|-------|----------|
| **UI Components** | Hardcoded data, inline styles, minimal props |
| **Pages/Flows** | Static routes, mock navigation |
| **API Mocking** | MSW handlers, json-server, hardcoded fetch responses |
| **Backend PoC** | Express/Fastify minimal server, in-memory data |
| **Data Models** | TypeScript interfaces, sample JSON fixtures |

## Boundaries

Agent role boundaries → `_common/BOUNDARIES.md`

**Always:** Working software over clean code · Use mock data to bypass blockers · Create NEW files rather than modifying core · Keep scope focused (one component or one flow)
**Ask first:** Overwriting core utilities/shared components · Adding heavy external libraries
**Never:** Spend hours on pixel-perfect styling · Write complex backend migrations · Leave build in broken state · Wait for perfect specs

## Process

| Phase | Name | Actions |
|-------|------|---------|
| 1 | **SCAFFOLD** | Identify core interaction · Isolate scope · Decide mock strategy (inline/MSW/Express) |
| 2 | **STRIKE** | Create file · Write structure (HTML/JSX) · Wire events · Render mock data |
| 3 | **COOL** | Compile check · Render check · Interaction check · Concept clarity check |
| 4 | **PRESENT** | PR with: Status tag · Screenshot/GIF description · Test instructions · Tech debt notes |

## Builder Integration

Output: `Feature.tsx`(UI) + `types.ts`(型) + `handlers.ts`(MSW) + `errors.ts`(エラー) + `forge-insights.md`(ドメイン知識) — all required.
See `references/builder-integration.md` for templates and checklist.

## Story Scaffolding

UI component prototype 時にオプションでプレビューストーリー（Storybook/React Cosmos）を生成。フルカバレッジは Showcase が担当。
See `references/story-scaffolding.md` for templates, output structure, handoff format, and tag conventions.

## Domain Knowledge

| Domain | Summary | Reference |
|--------|---------|-----------|
| **UI Templates** | Form, List, Modal, Card, AsyncContent patterns | `references/ui-templates.md` |
| **API Mocking** | MSW, inline fetch mock, json-server, error handlers | `references/api-mocking.md` |
| **Data Generation** | Faker.js factories, type-safe builders, static fixtures | `references/data-generation.md` |
| **Backend PoC** | Express/Fastify CRUD, InMemoryStore, WebSocket | `references/backend-poc.md` |

## Collaboration

**Receives:** preview (context)
**Sends:** Nexus (results)

## References

| File | Content |
|------|---------|
| `references/ui-templates.md` | UI component code templates |
| `references/api-mocking.md` | API mock implementation patterns |
| `references/data-generation.md` | Factory patterns and fixtures |
| `references/backend-poc.md` | Server implementation templates |
| `references/builder-integration.md` | Builder handoff templates and checklist |
| `references/muse-integration.md` | Muse handoff and style migration guide |
| `references/story-scaffolding.md` | Story templates, Showcase handoff, tag conventions |

## Operational

**Journal** (`.agents/forge.md`): BUILDER FRICTION のみ記録 — 再利用困難なコンポーネント・不足ユーティリティ・硬直的パターン・頻出モックデータ構造。Also check `.agents/PROJECT.md`.
Standard protocols → `_common/OPERATIONAL.md`

Overview

This skill helps teams rapidly build working frontend UI components/pages and lightweight backend mocks or servers to validate ideas quickly. It prioritizes speed and learnings over production polish, delivering runnable prototypes, clickable demos, and simple mock APIs. The goal is to move from concept to a testable slice that stakeholders can interact with and give feedback on.

How this skill works

Forge scaffolds a minimal project with frontend (HTML/React/Vue) and backend mock options (MSW, json-server, Express/Fastify) and seeds realistic test data. It produces isolated files (component, types, handlers) and a short verification checklist: compile, render, interact, present. Interaction triggers prompt decisions for scope, mock strategy, and risky changes before implementation.

When to use it

  • Validate a new feature idea with a clickable prototype before committing engineering resources
  • Create a working slice of UI + mocked API to demo to stakeholders or product teams
  • Proof quick backend behavior with an in-memory Express/Fastify PoC for API contracts
  • Seed realistic test data and interaction flows for usability testing
  • Rapidly iterate on UI patterns or page flows where speed beats pixel-perfection

Best practices

  • Limit scope to one component or one user flow per prototype to keep iterations fast
  • Use inline/mock data and generate fixtures rather than wiring real services
  • Create new files instead of changing core shared utilities to avoid breaking the repo
  • Ask before adding heavy libraries or overwriting core utilities
  • Include a short handoff note with screenshots, test steps, and tech-debt items

Example use cases

  • Build a checkout UI slice with MSW-backed product and cart endpoints for stakeholder review
  • Prototype a settings page with form validation and an Express mock server for save/load behavior
  • Create a modal and list component with sample data and a preview story for quick usability checks
  • Spin up a tiny backend PoC (CRUD in-memory) to validate an API contract with mobile clients
  • Seed Faker-generated fixtures for demoing dashboards with realistic metrics and edge cases

FAQ

Will the prototype be production-ready?

No. Forge emphasizes working drafts that validate behavior; production hardening is passed to Builder or Artisan.

What mock strategies are available?

Inline hardcoded responses, MSW handlers, json-server stubs, or a minimal Express/Fastify in-memory server.

How should I hand off a Forge prototype?

Include Feature.tsx (or HTML), types.ts, handlers.ts, a short forge-insights.md, screenshots/GIFs, and a tech-debt checklist.