app-builder

A project starter that chooses a suitable technology setup and creates the initial structure for a website, web app, API, mobile app, command-line tool, game, or online shop.

In plain words
What is it for?
Use it to bootstrap projects with options such as Next.js, Vite, Nuxt, Astro, FastAPI, Django, Laravel, React Native, or Flutter.
Why use it?
It removes the need to decide from scratch which framework and project layout to use when starting development.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/softspark/ai-toolkit/app-builder
Any agent
npx skills add softspark/ai-toolkit --skill app-builder
Clone the repo
git clone --depth 1 https://github.com/softspark/ai-toolkit

Made for: Claude Code, Codex.

Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,650 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original 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 $0.00046 $0.01650
Opus 5 $0.00023 $0.00825
Sonnet 5 $0.00009 $0.00330
Haiku 4.5 $0.00005 $0.00165

Measured 2d ago against content hash cb89e18571e5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

app-builder scanned grade A with 0 findings 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 2d 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.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

app/skills/app-builder/SKILL.md · 213 lines

How it starts

The opening of the file, as written. The whole thing — 213 lines — stays where its author put it; the contents beside it link to each section on GitHub.

App Builder Skill

Project Type Detection

Keywords Project Type Primary Agents
landing, website, marketing Static Site frontend-specialist
dashboard, admin, crud Web App frontend + backend
api, rest, graphql API Only backend-specialist
mobile, ios, android Mobile App mobile-developer
cli, command, terminal CLI Tool backend-specialist
game, unity, godot Game game-developer
ai, ml, rag AI/ML ai-engineer
e-commerce, shop, store E-commerce backend + frontend

Tech Stack Selection (2025)

Web Applications

Scenario Stack
Full-stack, SSR Next.js 14+ (App Router)
SPA with API React + Vite
Vue ecosystem Nuxt 3
Static/Blog Astro
E-commerce Next.js + Medusa/Shopify

Mobile Applications

Scenario Stack
Cross-platform (JS team) React Native + Expo
Cross-platform (any) Flutter
iOS only SwiftUI
Android only Kotlin + Jetpack Compose

Backend/API

Scenario Stack
Node.js, edge-ready Hono
Node.js, high perf Fastify
Python, async FastAPI
PHP, full-featured Laravel
E-commerce Magento/Sylius/PrestaShop

Database

Scenario Stack
General purpose PostgreSQL
Serverless Neon (PG), Turso (SQLite)
Document store MongoDB
Vector search PostgreSQL + pgvector
Cache Redis / Upstash

Project Templates

Next.js Full-Stack

project/
├── src/
│   ├── app/              # App Router
│   │   ├── (auth)/       # Auth group
│   │   ├── api/          # API routes
│   │   ├── layout.tsx
│   │   └── page.tsx
│   ├── components/       # Shared components
│   │   └── ui/           # UI primitives
│   ├── lib/              # Utilities
│   └── server/           # Server-only code
├── prisma/               # Database schema
├── public/
├── next.config.ts
├── tailwind.config.ts
└── package.json

Read the full file on GitHub · 213 lines

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. 2d ago First seen · 213 lines · 46 tokens per session scan A cb89e18571e5

Subscribe to this mod's changes

app-builder is a skill published in the GitHub repository softspark/ai-toolkit (167 stars, last pushed 4d ago), licensed Apache-2.0. It adds 46 tokens to every session and 1,650 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.