application-config

A set of setup patterns for KoaApplication, a Node.js framework for building HTTP servers. It shows how to configure ports, routers, sessions, static files, request parsing, events, and server-sent events.

In plain words
What is it for?
Setting up a Koa server, configuring environment-specific options, serving static files, managing sessions, parsing request bodies, and enabling server-sent events.
Why use it?
It gives developers a consistent starting point for configuring an application across development and production. It also highlights settings that affect public access and session security.

Cursor rule for Codex

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 rules/axiosleo/node-koapp/application-config
Clone the repo
git clone --depth 1 https://github.com/AxiosLeo/node-koapp

Made for: Codex.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 356 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 $0.00000 $0.00356
Opus 5 $0.00000 $0.00178
Sonnet 5 $0.00000 $0.00071
Haiku 4.5 $0.00000 $0.00036

Measured yesterday against content hash c47e0e0a8432, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

application-config 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 yesterday.

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/rules/application-config.mdc · 63 lines

What it actually says

Application Configuration

KoaApplication Setup

Standard HTTP server configuration:

const { KoaApplication, Router } = require("@axiosleo/koapp");

const app = new KoaApplication({
  port: 8080,
  listen_host: "localhost", // Use '0.0.0.0' for public access
  debug: false,
  routers: [router1, router2],

  // Session configuration
  session: {
    maxAge: 1296000000, // 15 days in ms
    httpOnly: true,
    signed: true,
    rolling: false,
    renew: true,
  },

  // Static file serving
  static: {
    rootDir: "./public",
    // uploadDir: './public/upload' // Optional upload directory
  },

  // Body parser options
  body_parser: {},

  // Server-Sent Events
  sse: false, // or { pingInterval: 60000, closeEvent: "close" }
});

app.start();

Environment-Specific Configuration

  • Use debug: true for development
  • Set listen_host: '0.0.0.0' for production deployment
  • Configure session security based on environment
  • Enable HTTPS in production with secure: true for sessions

Application Events

Applications emit events that can be handled:

  • starting - Before server starts
  • response - After each response

Required Node.js Version

Minimum Node.js version: 16.0.0 (as specified in package.json)

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. yesterday First seen · 63 lines · 356 tokens per session scan A c47e0e0a8432

Subscribe to this mod's changes

application-config is a cursor rule published in the GitHub repository AxiosLeo/node-koapp (129 stars, last pushed 18d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 356 tokens. 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 2026-08-30.