bun

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/bebiksior/httpworkbench/bun

Clone the repo

git clone --depth 1 https://github.com/bebiksior/httpworkbench

Made for: Cursor.

Per session 0 Nothing until a file matches its globs; then the whole rule loads.

When invoked 747 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. Scan, not verified.

Origin unknown 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	$0.00000	$0.00747
Opus 5	$0.00000	$0.00374
Sonnet 5	$0.00000	$0.00149
Haiku 4.5	$0.00000	$0.00075

Measured today against content hash d2a17c0be710, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

bun 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 today.

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.

.cursor/rules/bun.mdc · 112 lines

How it starts

The opening of the file, as written. The whole thing — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Default to using Bun instead of Node.js.

Use bun <file> instead of node <file> or ts-node <file>
Use bun test instead of jest or vitest
Use bun build <file.html|file.ts|file.css> instead of webpack or esbuild
Use bun install instead of npm install or yarn install or pnpm install
Use bun run <script> instead of npm run <script> or yarn run <script> or pnpm run <script>
Bun automatically loads .env, so don't use dotenv.

APIs

Bun.serve() supports WebSockets, HTTPS, and routes. Don't use express.
bun:sqlite for SQLite. Don't use better-sqlite3.
Bun.redis for Redis. Don't use ioredis.
Bun.sql for Postgres. Don't use pg or postgres.js.
WebSocket is built-in. Don't use ws.
Prefer Bun.file over node:fs's readFile/writeFile
Bun.$ls instead of execa.

Testing

Use bun test to run tests.

import { test, expect } from "bun:test";

test("hello world", () => {
  expect(1).toBe(1);
});

Frontend

Use HTML imports with Bun.serve(). Don't use vite. HTML imports fully support React, CSS, Tailwind.

Server:

import index from "./index.html"

Bun.serve({
  routes: {
    "/": index,
    "/api/users/:id": {
      GET: (req) => {
        return new Response(JSON.stringify({ id: req.params.id }));
      },
    },
  },
  // optional websocket support
  websocket: {
    open: (ws) => {
      ws.send("Hello, world!");
    },
    message: (ws, message) => {
      ws.send(message);
    },
    close: (ws) => {
      // handle close
    }
  },
  development: {
    hmr: true,
    console: true,
  }
})

HTML files can import .tsx, .jsx or .js files directly and Bun's bundler will transpile & bundle automatically. <link> tags can point to stylesheets and Bun's CSS bundler will bundle.

<html>
  <body>
    <h1>Hello, world!</h1>
    <script type="module" src="./frontend.tsx"></script>
  </body>
</html>

With the following frontend.tsx:

Read the full file on GitHub · 112 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.

today First seen · 112 lines · 0 tokens per session scan A d2a17c0be710

Subscribe to this mod's changes

bun is a cursor rule published in the GitHub repository bebiksior/httpworkbench (45 stars, last pushed 11d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 747 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 2026-09-01.

Getting it into your agent

What it costs to keep this loaded

Grade A, and why

Nothing flagged

How it starts

APIs

Testing

Frontend

What this file has done since we first saw it

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