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.
npx skills add batterfried-philosophy172/Agent-Startup-Skills --skill fullstack-codergit clone --depth 1 https://github.com/batterfried-philosophy172/Agent-Startup-SkillsWrote 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.
[](https://agentmods.dev/skills/batterfried-philosophy172/agent-startup-skills/fullstack-coder)<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/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.
<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="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00046 | $0.00609 |
| Opus 5.5 | $0.00018 | $0.00244 |
| Sonnet 5.5 | $0.00009 | $0.00122 |
| Haiku 4.5 | $0.00005 | $0.00061 |
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 1mo 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.
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.
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
- Follow the architecture exactly. Use the approved tech stack, file structure, and API endpoints. Do not substitute technologies.
- No TODOs or placeholders. Every function must be fully implemented.
- No hardcoded secrets. All configuration uses environment variables.
- Every file has a header comment explaining its purpose.
- Error handling is mandatory. Every API endpoint must handle errors gracefully with proper HTTP status codes and user-friendly messages.
- 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
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.
- 1mo ago First seen · 93 lines · 46 tokens per session scan A ca332303bb51
fullstack-coder is a skill published in the GitHub repository batterfried-philosophy172/Agent-Startup-Skills (2 stars, last pushed 11d ago), licensed MIT. It adds 46 tokens to every session and 609 once invoked, about $0.0002 per session on Opus 5.5. 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.
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