Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/ValorVie/custom-skillsnpx agentmods add skills/valorvie/custom-skills/bun-developmentWrote 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.
[](https://agentmods.dev/skills/valorvie/custom-skills/bun-development)<a href="https://agentmods.dev/skills/valorvie/custom-skills/bun-development"><img src="https://agentmods.dev/badge/skills/valorvie/custom-skills/bun-development/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.
<a href="https://agentmods.dev/skills/valorvie/custom-skills/bun-development"><img src="https://agentmods.dev/badge/skills/valorvie/custom-skills/bun-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00035 | $0.03998 |
| Opus 5 | $0.00017 | $0.01999 |
| Sonnet 5 | $0.00007 | $0.00800 |
| Haiku 4.5 | $0.00003 | $0.00400 |
Grade C, and why
bun-development scanned grade C with 2 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Recursive force deletehighDestructive command
rm -rf with a variable or a broad path is one typo away from removing the wrong tree.
trap 'rm -rf "$tmpdir"' EXIT Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -fsSLo "$tmpdir/bun-install.sh" https://bun.sh/install This is a copy
95% identical to bun-development — 24 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 707 lines — stays where its author put it; the contents beside it link to each section on GitHub.
⚡ Bun Development
Fast, modern JavaScript/TypeScript development with the Bun runtime, inspired by oven-sh/bun.
When to Use This Skill
Use this skill when:
- Starting new JS/TS projects with Bun
- Migrating from Node.js to Bun
- Optimizing development speed
- Using Bun's built-in tools (bundler, test runner)
- Troubleshooting Bun-specific issues
1. Getting Started
1.1 Installation
# macOS / Linux
brew install oven-sh/bun/bun
# Alternative: download the official installer, inspect it, then execute it
tmpdir="$(mktemp -d)"
trap 'rm -rf "$tmpdir"' EXIT
curl -fsSLo "$tmpdir/bun-install.sh" https://bun.sh/install
cat "$tmpdir/bun-install.sh" # review the full installer before executing
bash "$tmpdir/bun-install.sh"
# Windows
powershell -NoProfile -Command "Invoke-WebRequest https://bun.sh/install.ps1 -OutFile $env:TEMP\\bun-install.ps1; Get-Content $env:TEMP\\bun-install.ps1 -TotalCount 120; powershell -ExecutionPolicy Bypass -File $env:TEMP\\bun-install.ps1"
# Homebrew
brew tap oven-sh/bun
brew install bun
# npm (if needed)
npm install -g bun
# Upgrade
bun upgrade
1.2 Why Bun?
| Feature | Bun | Node.js |
|---|---|---|
| Startup time | ~25ms | ~100ms+ |
| Package install | 10-100x faster | Baseline |
| TypeScript | Native | Requires transpiler |
| JSX | Native | Requires transpiler |
| Test runner | Built-in | External (Jest, Vitest) |
| Bundler | Built-in | External (Webpack, esbuild) |
2. Project Setup
2.1 Create New Project
# Initialize project
bun init
# Creates:
# ├── package.json
# ├── tsconfig.json
# ├── index.ts
# └── README.md
# With specific template
bun create <template> <project-name>
# Examples
bun create react my-app # React app
bun create next my-app # Next.js app
bun create vite my-app # Vite app
bun create elysia my-api # Elysia API
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.
- 9d ago First seen · 707 lines · 35 tokens per session scan C b800aa943321
bun-development is a skill published in the GitHub repository ValorVie/custom-skills (5 stars, last pushed yesterday), licensed MIT. It adds 35 tokens to every session and 3,998 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it C with 2 findings (recursive force delete, makes network calls). It is 95% identical to bun-development, differing in 24 lines, and is treated as a copy.
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typescript-patterns
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