app-builder

app-builder is a skill for Claude Code from sawrus/agent-guides. It costs 26 tokens per session (1,208 once invoked), scanned A, original, MIT.

A project scaffolding skill that chooses a technology stack and creates the starting structure for a full-stack application. It supports web apps, APIs, mobile apps, command-line tools, and monorepos, which are repositories containing multiple related apps or packages.

In plain words
What is it for?
Starting dashboards, SaaS products, REST APIs, mobile apps, command-line tools, and projects with multiple applications.
Why use it?
It removes the initial guesswork of choosing tools, folders, and supporting services for a new application.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit Starting dashboards, SaaS products, REST APIs, mobile apps, command-line tools, and projects with multiple applications.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sawrus/agent-guides/app-builder
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.

Any agent
npx skills add sawrus/agent-guides --skill app-builder
Clone the repo
git clone --depth 1 https://github.com/sawrus/agent-guides

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for app-builder

README.md
[![agentmods](https://agentmods.dev/badge/skills/sawrus/agent-guides/app-builder/github.svg)](https://agentmods.dev/skills/sawrus/agent-guides/app-builder)
Your own site
<a href="https://agentmods.dev/skills/sawrus/agent-guides/app-builder"><img src="https://agentmods.dev/badge/skills/sawrus/agent-guides/app-builder/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for app-builder

Your own site · 80×15
<a href="https://agentmods.dev/skills/sawrus/agent-guides/app-builder"><img src="https://agentmods.dev/badge/skills/sawrus/agent-guides/app-builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 26 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,208 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 5.1 $0.00026 $0.01208
Opus 5 $0.00013 $0.00604
Sonnet 5 $0.00005 $0.00242
Haiku 4.5 $0.00003 $0.00121

Measured 7d ago against content hash 590225133391, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, 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 7d 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.

areas/software/full-stack/skills/app-builder/SKILL.md · 136 lines

How it starts

The opening of the file, as written. The whole thing — 136 lines — stays where its author put it; the contents beside it link to each section on GitHub.

App Builder Skill

Analyzes requests, selects tech stack, scaffolds structure, coordinates agents.

Project Type Detection

Keywords Project Type Default Stack
dashboard, admin, crud, internal tool Full-stack web Next.js + Prisma + Postgres
SaaS, subscription, billing SaaS web Next.js + Stripe + Clerk + Prisma
API, microservice, backend REST API FastAPI (Python) or Express (Node)
mobile app, iOS, Android Mobile React Native + Expo
CLI, command line, terminal CLI tool Node.js + Commander or Python + Typer
monorepo, multiple apps Monorepo Turborepo + pnpm

Default 2025 Stack

Frontend:  Next.js 15 (App Router) + TypeScript strict + Tailwind + shadcn/ui
Backend:   Next.js Server Actions (collocated) or FastAPI (standalone API)
Database:  PostgreSQL via Prisma (JS) or SQLAlchemy async (Python)
Auth:      Clerk (SaaS/Web) or custom JWT (API-only)
Testing:   Vitest + Playwright (JS) | pytest + Playwright (Python)
Deploy:    Vercel (Next.js) | Railway/Render (FastAPI)

Next.js Full-Stack Directory Structure

src/
├── app/                    # Routes only — thin layer
│   ├── layout.tsx
│   ├── (auth)/             # Route group — auth pages
│   ├── (dashboard)/        # Route group — protected pages
│   └── api/[resource]/route.ts
│
├── features/               # Feature-based modules (primary work happens here)
│   ├── orders/
│   │   ├── components/     # UI — OrderCard, OrderList
│   │   ├── actions.ts      # Server Actions — createOrder, cancelOrder
│   │   ├── queries.ts      # Data fetching — getOrder, listOrders
│   │   └── types.ts
│   └── auth/
│       ├── components/
│       ├── actions.ts
│       └── queries.ts
│
├── shared/
│   ├── components/ui/      # Reusable: Button, Input, Card
│   └── lib/                # Utilities, formatters, constants
│
└── server/                 # Server-only (never imported in client components)
    ├── db/                 # Prisma client
    ├── auth/               # Auth config
    └── services/           # External API integrations

Read the full file on GitHub · 136 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. 7d ago First seen · 136 lines · 26 tokens per session scan A 590225133391

Subscribe to this mod's changes

app-builder is a skill published in the GitHub repository sawrus/agent-guides (17 stars, last pushed 10d ago), licensed MIT. It adds 26 tokens to every session and 1,208 once invoked, about $0.0001 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 2026-09-03.