> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sailresearch.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Sailboxes

> Efficient cloud environments for long-horizon agents

This page is a high-level guide to Sailboxes, efficient cloud environments
specifically designed for long-horizon agents.

See the [Sailbox reference](/sailbox-sdk) for reference documentation on
Sailboxes.

## What are Sailboxes and why should I use them?

Sailboxes are persistent Linux VMs designed for long-horizon agents. They can be dynamically
provisioned in seconds and are the perfect cloud environment for any agent.
They provide a number of advantages over other sandboxing providers:

* Only pay for the exact portion of CPU, memory, and disk you actually use within a
  sandbox. Agents spend most of their time blocked on I/O so sailboxes are significantly more
  cost effective than other providers (see comparison below).
* Use as much (or as little) compute as you need. Even though you only pay for the resources you actually use,
  each sailbox is eligible to consume a practically unbounded amount of CPU or memory, ensuring your agents are never
  bottlenecked on hardware.
* Fine grained network control and automatic credential injection. Fully isolate your agents from your API keys, and grant
  permissions seamlessly across swarms of sailboxes.
* Pause, resume, and fork all sandbox state, including open network connections, for any
  duration. In-flight work survives the pause with no save/restore code on
  your side.
* Automatically sleep Sailboxes while waiting on Sail inference calls.

<Note>
  Sailboxes are currently in beta. APIs and operational behavior may change as
  we stabilize the product.
</Note>

## Provider comparison

| Provider       | vCPU price                      | Sleep during inference | Max runtime    | Memory snapshots | Network snapshots                                  | Local NVMe disks | Docker-in-Docker | Start/resume time |
| -------------- | ------------------------------- | ---------------------- | -------------- | ---------------- | -------------------------------------------------- | ---------------- | ---------------- | ----------------- |
| Sailboxes      | \$0.015/actively-used vCPU-hour | Yes                    | No fixed limit | Yes              | Yes, open connections survive for up to 10 minutes | Yes              | Yes              | \<3s              |
| Modal          | \$0.071/reserved-vCPU-hour      | No                     | 24 hours       | Alpha            | No                                                 | No               | Alpha            | \<500ms           |
| E2B            | \$0.0504/reserved-vCPU-hour     | No                     | 24 hours       | Yes              | No                                                 | No               | Yes              | \<1s              |
| Vercel Sandbox | \$0.128/reserved-vCPU-hour      | No                     | 5 hours        | No               | No                                                 | Yes              | Yes              | \<1s              |
| Daytona        | \$0.0504/reserved-vCPU-hour     | No                     | No fixed limit | Experimental     | No                                                 | Yes              | Yes              | \<500ms           |

## Start here

* [Quickstart](/sailboxes-quickstart): create a Sailbox, run commands, expose a
  service, and clean up.
* [Pricing](/sailboxes-pricing): understand observed-usage billing dimensions and
  per-hour rates.
* [Images](/sailboxes-images): choose a base image and build custom images with
  packages, commands, environment variables, and local files.
* [Networking](/sailboxes-networking): expose HTTP services, raw TCP ports, and
  SSH from a Sailbox.
* [Filesystem](/sailboxes-filesystem): read and write files at runtime, stream
  large files, and decide what belongs in an image.
* [Lifecycle](/sailboxes-lifecycle): checkpoint, start from checkpoint, pause,
  sleep, resume, upgrade, and terminate Sailboxes.