# agentOS vs Sandbox

> Source: `src/content/docs/agent-os/versus-sandbox.mdx`
> Canonical URL: https://rivet.dev/docs/agent-os/versus-sandbox
> Description: When to use the lightweight agentOS VM, a full sandbox, or both together.

---
- **agentOS** is a lightweight VM that runs inside your process. Near-zero cold start, low memory, direct backend integration via [host tools](/docs/agent-os/tools).
- **Sandboxes** are full Linux environments with root access, system packages, and native binary support.
- **You can use both.** agentOS works with sandboxes through [sandbox mounting](/docs/agent-os/sandbox). Agents run in the lightweight VM by default and spin up a full sandbox on demand.

## Comparison

|  | agentOS VM | Full Sandbox |
|---|---|---|
| **Cost** | Very low. Runs in your process. | Pay per second of uptime. |
| **Startup** | Near-zero cold start (~6 ms). | Seconds to spin up. |
| **Backend integration** | Direct. [Host tools](/docs/agent-os/tools) call your functions with zero latency. | Indirect. Requires network calls back to your backend. |
| **API keys** | Stay on the server via the [LLM gateway](/docs/agent-os/llm-gateway). | Must be injected into the sandbox environment. |
| **Permissions** | Granular, deny-by-default. | Coarse-grained (container-level). |
| **Infrastructure** | `npm install` | Vendor account + API keys. |
| **Best for** | Coding, file manipulation, scripting, API calls, orchestration. | Browsers, desktop automation, native compilation, dev servers. |

## When to use each

### agentOS VM

Use the lightweight VM for most agent workloads:

- Coding and file editing
- Running scripts and CLI tools
- Calling APIs and services via host tools
- Multi-agent orchestration and workflows
- Tasks where backend integration matters (permissions, tool access, LLM routing)

### Full sandbox

Spin up a sandbox when the workload needs a real Linux kernel:

- Browsers and desktop automation (Playwright, Puppeteer, Selenium)
- Heavy compilation and native toolchains
- Dev servers with hot reload, databases, and system ports
- GUI applications and VNC sessions

### Both together

Use agentOS with [sandbox mounting](/docs/agent-os/sandbox) for workflows that need both:

- Agent runs in the agentOS VM with full access to host tools and permissions
- Sandbox spins up on demand for heavy tasks
- Sandbox filesystem is mounted into the VM as a native directory
- Agent reads and writes sandbox files the same way it reads local files

_Source doc path: /docs/agent-os/versus-sandbox_
