---
title: "SDK Quickstart - Docs"
label: "SDK Quickstart"
description: "Deploy with the Buildfunctions SDK"
---

## Get Started

### First Install

```bash npm
npm install buildfunctions
```
```bash yarn
yarn add buildfunctions
```
```bash pnpm
pnpm add buildfunctions
```
```bash pip
pip install buildfunctions
```

> **Note**
>
> Mojo coming soon! 🔥

### Create an API token

Create an API token at [https://www.buildfunctions.com/settings](https://www.buildfunctions.com/settings)

![Web Dashboard](/assets/images/dashboard_settings.jpeg)

### Authenticate

Write your agent app code and authenticate with the Buildfunctions SDK:

```javascript
...
const apiToken = process.env.BUILDFUNCTIONS_API_TOKEN
if (!apiToken) {
  return new NextResponse('Missing BUILDFUNCTIONS_API_TOKEN', { status: 500 })
}

// Authenticate with a Buildfunctions API token
await Buildfunctions({ apiToken })
...
```

### Create a GPU Sandbox and run inference

```javascript
...
// Create a GPU Sandbox with Python and PyTorch
const sandbox = await GPUSandbox.create({
  name: 'secure-agent-action',
  memory: '50000MB',
  gpu: 'T4G',
  timeout: 1200, // 24 hours max
  language: 'python', // language available within sandbox
  code: inferenceCode, // inline code or path to file
  requirements: ['transformers', 'torch', 'accelerate'], // python dependencies
  model: '/path/to/models/Qwen/Qwen3-8B', // path to folder with models can be local or remote (e.g., Hugging Face)
})

// Run inference within hardware-isolated VM (full GPU access)
const result = await sandbox.run()
...

```

```python
...
sandbox = await GPUSandbox.create({
    "name": "my-gpu-sandbox",
    "language": "python",
    "memory": 10000,
    "timeout": 300,
    "vcpus": 6,
    "code": "./gpu_sandbox_code.py",
    "model": "/path/to/models/Qwen/Qwen3-8B",
    "requirements": "torch",
})

result = await sandbox.run()
...

```

### Add Runtime Controls

Help keep your agent running unattended. Runtime Controls wrap function calls with composable guardrails — no API key required.

```javascript
import { RuntimeControls } from 'buildfunctions'

const controls = RuntimeControls.create({
  maxToolCalls: 50,
  timeoutMs: 30_000,
  retry: { maxAttempts: 3, initialDelayMs: 200, backoffFactor: 2 },
  loopBreaker: { warningThreshold: 5, quarantineThreshold: 8, stopThreshold: 12 },
  onEvent: (event) => console.log(`[controls] ${event.type}: ${event.message}`),
})

const guardedFetch = controls.wrap({
  toolName: 'api-call',
  runKey: 'agent-run-1',
  destination: 'https://api.example.com',
  run: async ([payload]) => {
    const res = await fetch('https://api.example.com/data', {
      method: 'POST',
      body: JSON.stringify(payload),
    })
    return res.json()
  },
})

const result = await guardedFetch({ query: 'latest results' })

// Reset budget counters when starting a new run
await controls.reset('agent-run-1')
```

Works standalone or combined with Buildfunctions hardware-isolated sandboxes. For backend-specific integrations, validate behavior with your own integration tests. See the full [Runtime Controls](/docs/runtime-controls) docs for all control layers.

> **Note**
>
> Buildfunctions is currently in its beta stage. If you encounter any issues or have specific syntax requirements, please reach out and [contact us](https://www.buildfunctions.com/contact), and we’ll work to address them.