What is claude-node-setup AGENTS.md?

Project instructions for a library of guides that help AI agents develop Node.js applications with the Fastify web framework.

Use them when working on Fastify routes, Node.js code, API documentation, tests, linting, or formatting in this repository.

They explain the project's tools, file locations, commands, and coding rules so changes fit the existing codebase.

How jesus-seijas-sp/claude-node-setup configures Codex and OpenCode

Reuse

Borrowing it

Nothing to install: this file belongs to jesus-seijas-sp/claude-node-setup. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/jesus-seijas-sp/claude-node-setup/main/AGENTS.md

Clone the repo

git clone --depth 1 https://github.com/jesus-seijas-sp/claude-node-setup

Made for: Codex, OpenCode.

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.

README.md

[![agentmods](https://agentmods.dev/badge/instructions/jesus-seijas-sp/claude-node-setup/agents-md/github.svg)](https://agentmods.dev/instructions/jesus-seijas-sp/claude-node-setup/agents-md)

Your own site

<a href="https://agentmods.dev/instructions/jesus-seijas-sp/claude-node-setup/agents-md"><img src="https://agentmods.dev/badge/instructions/jesus-seijas-sp/claude-node-setup/agents-md/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.

Your own site · 80×15

<a href="https://agentmods.dev/instructions/jesus-seijas-sp/claude-node-setup/agents-md"><img src="https://agentmods.dev/badge/instructions/jesus-seijas-sp/claude-node-setup/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 861 This file is loaded in full into every session.

When invoked 861 The same file — it is already loaded in full.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00861	$0.00861
Opus 5.5	$0.00344	$0.00344
Sonnet 5.5	$0.00172	$0.00172
Haiku 4.5	$0.00086	$0.00086

Measured 2mo ago against content hash 9378c7879873, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

claude-node-setup AGENTS.md 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 2mo 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.

AGENTS.md · 96 lines

How it starts

The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Claude Code — Project Instructions

This file provides guidance to AI coding agents (focuses in Claude Code) working in this repository.

What this repository is

A skills library for AI-assisted Node.js/JavaScript development with Fastify. Skills are Markdown documents that instruct AI agents how to write correct, idiomatic code for this stack.

Skills live under .claude/skills/<skill-name>/ and are the primary content of this repo.

Stack

Concern	Technology
Runtime	Node.js (ESM, `"type": "module"`)
Language	JavaScript
Web framework	Fastify
Logger	Pino (via `fastify.log`)
API docs	swagger-jsdoc + @fastify/swagger
Test runner	`node --test` (built-in)
Linter	ESLint
Formatter	Prettier

Skills

Each skill is a self-contained guide. Read the relevant skill before writing code in that area.

Skill	Path	Purpose
`fastify`	`.claude/skills/fastify/SKILL.md`	Correct Fastify patterns: plugins, routes, schemas, lifecycle hooks
`nodejs`	`.claude/skills/nodejs/SKILL.md`	Idiomatic Node.js/JavaScript: ESM, async, error handling, project structure, Swagger
`pino`	`.claude/skills/pino/SKILL.md`	Logging with Pino: levels, context, child loggers, structured logs
`documentation`	`.claude/skills/documentation/SKILL.md`	Producing Markdown docs and Mermaid diagrams
`security`	`.claude/skills/security/SKILL.md`	Secure coding: input validation, injection prevention, auth, safe error handling, HTTP headers

Common commands

Run from the repository root.

npm install          # Install dependencies
npm run lintfix      # ESLint --fix + Prettier
npm test             # Run all tests (node --test)

Run a single test file:

node --test test/features/users/users.router.test.js

Read the full file on GitHub · 96 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.

2mo ago First seen · 96 lines · 861 tokens per session scan A 9378c7879873

Subscribe to this mod's changes

claude-node-setup AGENTS.md is an instructions file published in the GitHub repository jesus-seijas-sp/claude-node-setup (10 stars, last pushed 8mo ago), licensed MIT. It adds 861 tokens to every session, about $0.0034 per session on Opus 5.5. 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 2026-08-31.

claude-node-setup AGENTS.md next to 6 instructions from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
claude-node-setup AGENTS.mdjesus-seijas-sp/claude-node-setup	Instructions file	10	8mo ago	MIT	A	861	Codex, OpenCode
vscode buildNext.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	9,719	GitHub Copilot
next.js AGENTS.mdvercel/next.js	Instructions file	143k	yesterday	MIT	A	7,461	Codex, OpenCode
langchain AGENTS.mdlangchain-ai/langchain	Instructions file	149k	yesterday	MIT	A	4,680	Codex, OpenCode
vscode oss-third-party-notices.instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	5,516	GitHub Copilot
vscode copilot-instructions.mdmicrosoft/vscode	Instructions file	195k	yesterday	MIT	A	3,093	GitHub Copilot
deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness	Instructions file	274k	2d ago	MIT	A	4,313	Codex, OpenCode

claude-node-setup: Instructions file for Codex