bun CLAUDE.md

bun CLAUDE.md is an instructions file for coding agents from oven-sh/bun. It costs 4,508 tokens per session, scanned B, original, no licence file.

A set of Claude Code instructions for the Bun project, a JavaScript runtime and toolkit. It covers how to build, run, test, and decide when a build is unnecessary.

In plain words
What is it for?
Use it while working in the oven-sh/bun repository. It helps with builds, test runs, and changes that can be checked without rebuilding.
Why use it?
It gives the coding agent project-specific commands and expectations, reducing mistakes when changing or testing Bun.

Instructions file

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 instructions/oven-sh/bun/claude-md
Clone the repo
git clone --depth 1 https://github.com/oven-sh/bun

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 bun CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/oven-sh/bun/claude-md.svg)](https://agentmods.dev/instructions/oven-sh/bun/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/oven-sh/bun/claude-md"><img src="https://agentmods.dev/badge/instructions/oven-sh/bun/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 4,508 This file is loaded in full into every session.
When invoked 4,508 The same file — it is already loaded in full.
Security scan B 1 finding. 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.04508 $0.04508
Opus 5 $0.02254 $0.02254
Sonnet 5 $0.00902 $0.00902
Haiku 4.5 $0.00451 $0.00451

Measured 6d ago against content hash 51bfba7963b0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade B, and why

bun CLAUDE.md scanned grade B with 1 finding 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 6d 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.

Unrestricted tool accessmediumExcessive agency

A wildcard tool grant or "run any command" leaves no least-privilege boundary at all.

- **Run any command with debug build**: `bun bd <command>`
CLAUDE.md · 241 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 6d ago First seen · 241 lines · 4,508 tokens per session scan B 51bfba7963b0

Subscribe to this mod's changes

bun CLAUDE.md is an instructions file published in the GitHub repository oven-sh/bun (95,879 stars, last pushed today), with no licence file. It adds 4,508 tokens to every session, about $0.0225 per session on Opus 5. A static security scan graded it B with 1 finding (unrestricted tool access). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.