# Deno — Secure Runtime for AI Agent Scripts

> Modern JavaScript/TypeScript runtime with built-in security, native TypeScript support, and web-standard APIs. Deno runs AI agent scripts safely with permission controls.

## Install

Save as a script file and run:

## Quick Use

```bash
# Install Deno
curl -fsSL https://deno.land/install.sh | sh
```

```typescript
// ai_agent.ts — run with: deno run --allow-net ai_agent.ts
const response = await fetch("https://api.anthropic.com/v1/messages", {
  method: "POST",
  headers: {
    "x-api-key": Deno.env.get("ANTHROPIC_API_KEY")!,
    "content-type": "application/json",
    "anthropic-version": "2023-06-01",
  },
  body: JSON.stringify({
    model: "claude-sonnet-4-20250514",
    max_tokens: 1024,
    messages: [{ role: "user", content: "Hello Claude!" }],
  }),
});

const data = await response.json();
console.log(data.content[0].text);
```

## What is Deno?

Deno is a modern JavaScript/TypeScript runtime created by Ryan Dahl (the original creator of Node.js). It fixes Node.js design mistakes with built-in TypeScript support, web-standard APIs (fetch, WebSocket, etc.), and a permission-based security model. For AI applications, Deno is ideal for running agent scripts safely — network, file, and environment access must be explicitly granted.

**Answer-Ready**: Deno is a secure JS/TS runtime by Node.js creator Ryan Dahl. Native TypeScript, web-standard APIs, permission-based security. Ideal for AI agent scripts with controlled access. Built-in formatter, linter, and test runner. 100k+ GitHub stars.

**Best for**: Developers writing AI agent scripts needing security controls. **Works with**: Any LLM API, MCP servers, Claude Code extensions. **Setup time**: Under 1 minute.

## Core Features

### 1. Permission-Based Security

```bash
# Explicit permissions — agent can only access what you allow
deno run --allow-net=api.anthropic.com --allow-env=ANTHROPIC_API_KEY agent.ts

# Deny all by default
deno run agent.ts  # Error: network access denied
```

### 2. Native TypeScript

```typescript
// No tsconfig, no build step, just run
interface AgentResponse {
  thought: string;
  action: string;
  result: string;
}

const response: AgentResponse = await runAgent(query);
```

### 3. Web Standard APIs

```typescript
// fetch, WebSocket, TextEncoder — all built in
const ws = new WebSocket("wss://stream.example.com");
ws.onmessage = (e) => console.log(e.data);

// ReadableStream for streaming LLM responses
const stream = response.body!.pipeThrough(new TextDecoderStream());
for await (const chunk of stream) {
  Deno.stdout.write(new TextEncoder().encode(chunk));
}
```

### 4. Built-in Toolchain

```bash
deno fmt          # Format code
deno lint         # Lint code
deno test         # Run tests
deno compile      # Compile to single binary
deno jupyter      # Jupyter notebook kernel
```

### 5. npm Compatibility

```typescript
// Use any npm package with npm: specifier
import Anthropic from "npm:@anthropic-ai/sdk";
import OpenAI from "npm:openai";
```

## Deno vs Node.js for AI Scripts

| Feature | Deno | Node.js |
|---------|------|---------|
| TypeScript | Native | Needs tsc/tsx |
| Security | Permission-based | Full access |
| fetch API | Built-in | Node 18+ |
| Package manager | URL imports + npm: | npm/yarn/pnpm |
| Single binary compile | Yes | pkg/nexe |
| Top-level await | Yes | ESM only |

## FAQ

**Q: Can I use npm packages?**
A: Yes, use `npm:package-name` imports. Most npm packages work out of the box.

**Q: Is Deno good for MCP servers?**
A: Yes, the permission model is perfect for MCP servers — grant only the access each server needs.

**Q: How does it compare to Bun?**
A: Bun focuses on speed and Node compatibility. Deno focuses on security and web standards. For AI agents, Deno's permission model is a significant advantage.

## Source & Thanks

> Created by [Ryan Dahl](https://github.com/denoland). Licensed under MIT.
>
> [denoland/deno](https://github.com/denoland/deno) — 100k+ stars

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## 快速使用

```bash
curl -fsSL https://deno.land/install.sh | sh
```

安全运行 TypeScript AI Agent 脚本，无需配置。

## 什么是 Deno？

Deno 是 Node.js 创始人打造的现代 JS/TS 运行时。原生 TypeScript、Web 标准 API、权限安全模型，适合运行 AI Agent 脚本。

**一句话总结**：安全 JS/TS 运行时，原生 TypeScript + 权限控制 + Web 标准 API，Node.js 创始人出品，AI Agent 脚本理想选择，100k+ stars。

**适合人群**：编写 AI Agent 脚本需要安全控制的开发者。

## 核心功能

### 1. 权限安全
网络/文件/环境变量访问需显式授权。

### 2. 原生 TypeScript
无需配置，直接运行 .ts 文件。

### 3. npm 兼容
`npm:` 前缀使用任意 npm 包。

## 常见问题

**Q: 能用 npm 包？**
A: 可以，`npm:package-name` 导入。

**Q: 适合写 MCP 服务器？**
A: 非常适合，权限模型完美匹配。

## 来源与致谢

> [denoland/deno](https://github.com/denoland/deno) — 100k+ stars, MIT

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Source: https://tokrepo.com/en/workflows/568daf2d-ffc9-4aa6-81d6-e17c843c9bd3
Author: Script Depot