pn-node-api

pn-node-api is a skill for Claude Code, Codex from perniemann/pnCore. It costs 41 tokens per session (1,547 once invoked), scanned A, original, MIT.

A guide to designing and implementing Node APIs, including routes, database access, configuration, secrets, errors, and request-response patterns.

In plain words
What is it for?
Use it when building or reviewing REST endpoints, changing database access, or refactoring Node backend configuration and error handling.
Why use it?
It helps teams make API behaviour consistent and avoid unclear routes, incorrect status codes, unsafe configuration, and fragile database code.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: positional $N argument.

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/perniemann/pncore/pn-node-api
Any agent
npx skills add perniemann/pnCore --skill pn-node-api
Clone the repo
git clone --depth 1 https://github.com/perniemann/pnCore

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 pn-node-api

README.md
[![agentmods](https://agentmods.dev/badge/skills/perniemann/pncore/pn-node-api.svg)](https://agentmods.dev/skills/perniemann/pncore/pn-node-api)
Your own site
<a href="https://agentmods.dev/skills/perniemann/pncore/pn-node-api"><img src="https://agentmods.dev/badge/skills/perniemann/pncore/pn-node-api.svg" alt="Measured on agentmods" height="20"></a>
Per session 41 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,547 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 5.1 $0.00041 $0.01547
Opus 5 $0.00020 $0.00773
Sonnet 5 $0.00008 $0.00309
Haiku 4.5 $0.00004 $0.00155

Measured 2d ago against content hash c60b05726356, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

pn-node-api 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.

packages/pn-core-mcp/content/skills/backend/pn-node-api/SKILL.md · 179 lines

How it starts

The opening of the file, as written. The whole thing — 179 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Node / API skill

When to use

  • Designing or implementing REST/API endpoints.
  • Adding or changing database access (queries, migrations, connections).
  • Setting up or refactoring env/config and secrets.
  • Reviewing backend error handling and safety.
  • Establishing consistent request/response patterns across an API.

Workflow

1. API design

Use clear resource names (nouns), appropriate HTTP methods, and standard status codes. Design the contract before writing implementation.

// Resource: /users
// Collection:  GET /users, POST /users
// Resource:    GET /users/:id, PATCH /users/:id, HTTP DELETE on /users/:id
// Sub-resource: GET /users/:id/orders

// Status codes — always be specific
// 201 Created (POST that creates a resource)
// 204 No Content (DELETE or PATCH with no body to return)
// 400 Bad Request (malformed syntax, wrong types)
// 401 Unauthorized (no valid credentials)
// 403 Forbidden (valid credentials, wrong permissions)
// 404 Not Found (resource doesn't exist)
// 422 Unprocessable (valid JSON, failed business rules / validation)
// 429 Too Many Requests (rate limited)
// 500 Internal Server Error (unexpected programmer error)

Document request/response shapes with OpenAPI or TypeScript interfaces before implementation. Reference pn-core://skills/backend/reference/api-design.md for full REST conventions, versioning, pagination, and anti-patterns.

2. Input validation

Validate at the route boundary — before any business logic executes.

import { z } from "zod";

export const CreateUserSchema = z.object({
  email: z.string().email().max(255).toLowerCase(),
  name: z.string().min(1).max(100).trim(),
  role: z.enum(["user", "admin"]).default("user"),
});

// In the route handler
const result = CreateUserSchema.safeParse(req.body);
if (!result.success) {
  throw new AppError("VALIDATION_FAILED", 422, "Invalid request data");
}
const validated = result.data; // TypeScript knows the shape

3. Config and secrets

Read the full file on GitHub · 179 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 · 179 lines · 41 tokens per session scan A c60b05726356

Subscribe to this mod's changes

pn-node-api is a skill published in the GitHub repository perniemann/pnCore (0 stars, last pushed 2d ago), licensed MIT. It adds 41 tokens to every session and 1,547 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 2026-09-03.