fullstack-coder

fullstack-coder is a skill for Claude Code, Codex from batterfried-philosophy172/Agent-Startup-Skills. It costs 46 tokens per session (609 once invoked), scanned A, a copy of fullstack-coder, MIT.

A full-stack coding skill for implementing an approved application design and database schema. It produces runnable code across the project's client, server, configuration, and data layers.

In plain words
What is it for?
Use it after the architecture and schema are approved to scaffold the project, implement database work and application features, and build the approved MVP.
Why use it?
It turns an agreed architecture and feature scope into complete code while requiring validation, error handling, environment-based configuration, and no unfinished placeholders.

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/batterfried-philosophy172/agent-startup-skills/fullstack-coder
Any agent
npx skills add batterfried-philosophy172/Agent-Startup-Skills --skill fullstack-coder
Clone the repo
git clone --depth 1 https://github.com/batterfried-philosophy172/Agent-Startup-Skills

Made for: Claude Code, Codex.

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 fullstack-coder

README.md
[![agentmods](https://agentmods.dev/badge/skills/batterfried-philosophy172/agent-startup-skills/fullstack-coder.svg)](https://agentmods.dev/skills/batterfried-philosophy172/agent-startup-skills/fullstack-coder)
Your own site
<a href="https://agentmods.dev/skills/batterfried-philosophy172/agent-startup-skills/fullstack-coder"><img src="https://agentmods.dev/badge/skills/batterfried-philosophy172/agent-startup-skills/fullstack-coder.svg" alt="Measured on agentmods" height="20"></a>
Per session 46 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 609 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00609
Opus 5 $0.00023 $0.00304
Sonnet 5 $0.00009 $0.00122
Haiku 4.5 $0.00005 $0.00061

Measured 5d ago against content hash ca332303bb51, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fullstack-coder 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 5d 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.

Origin

This is a copy

100% identical to fullstack-coder — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/fullstack-coder/SKILL.md · 93 lines

How it starts

The opening of the file, as written. The whole thing — 93 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Full-Stack Coder — Implementation Agent

Purpose

Write complete, runnable, production-quality code that exactly follows the approved architecture, schema, and MVP scope. No shortcuts, no placeholders.

When to Use

  • After architecture AND schema are approved
  • When implementing approved MVP features
  • Never before Phase 3 and Phase 4 of the SaaS Accelerator pipeline

Hard Rules

  1. Follow the architecture exactly. Use the approved tech stack, file structure, and API endpoints. Do not substitute technologies.
  2. No TODOs or placeholders. Every function must be fully implemented.
  3. No hardcoded secrets. All configuration uses environment variables.
  4. Every file has a header comment explaining its purpose.
  5. Error handling is mandatory. Every API endpoint must handle errors gracefully with proper HTTP status codes and user-friendly messages.
  6. Input validation is mandatory. Validate all user inputs on both client and server side.

Process

Step 1: Project Scaffold

Generate every file and folder from the architecture document. Start with configuration files: package.json, .env.example, config files.

Step 2: Database Layer

Implement the schema from Phase 4:

  • Migration files or ORM schema definitions
  • Database connection utility
  • Seed script for test data

Step 3: Backend API

Implement each API endpoint from the architecture document, one at a time:

  • Route handler
  • Input validation
  • Business logic
  • Error handling
  • Response formatting

Step 4: Authentication

Implement the full auth flow:

  • Registration (with password hashing)
  • Login (with session/token creation)
  • Protected route middleware
  • Logout

Step 5: Frontend

Implement each page/screen from the MVP scope:

  • Layout and navigation
  • Forms with client-side validation
  • API integration (data fetching and mutations)
  • Loading and error states
  • Responsive design

Step 6: Environment Configuration

Generate a complete .env.example with descriptions:

# Database
DATABASE_URL=postgresql://user:pass@localhost:5432/dbname

# Authentication
JWT_SECRET=your-secret-key-here
SESSION_EXPIRY=86400

# External Services
SMTP_HOST=smtp.example.com

Read the full file on GitHub · 93 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. 5d ago First seen · 93 lines · 46 tokens per session scan A ca332303bb51

Subscribe to this mod's changes

fullstack-coder is a skill published in the GitHub repository batterfried-philosophy172/Agent-Startup-Skills (2 stars, last pushed 2d ago), licensed MIT. It adds 46 tokens to every session and 609 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to fullstack-coder, differing in 0 lines, and is treated as a copy.

Related

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save

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export

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use

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