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

# Shell

Every box has a full Linux shell and runs on Debian by default.

You can access that shell either through the SDK or directly over SSH.

***

## SSH

Connect to a box with:

```bash theme={"system"}
ssh <box-id>@us-east-1.box.upstash.com
```

When prompted for a password, use your **Box API key**.

For example:

```bash theme={"system"}
ssh current-wasp-05510@us-east-1.box.upstash.com
```

<Tip>
  You can also copy this command from the **SSH** button on the box details page in the Upstash Console.
</Tip>

***

## API

### Run a shell command

A shell command resolves when the command finishes and gives you back the result and status.

```typescript theme={"system"}
const run = await box.exec.command("echo hello")

console.log(run.result) // "hello"
console.log(run.status) // "completed"
```

If you need additional system tools, install them with Debian's package manager inside the box.

```typescript theme={"system"}
await box.exec.command("sudo apt-get install <package>")
```

***

### Run a code snippet

You can execute code inside of a box:

```typescript theme={"system"}
const run = await box.exec.code({
  code: "console.log('hello')",
  lang: "js",
  timeout: 10_000,
})

console.log(run.output) // "hello"
console.log(run.exit_code) // "0"
```

***

### Check exit status

If the command fails, the run status will be `"failed"` and its result contains the stderr output.

```typescript theme={"system"}
const run = await box.exec.command("node -e 'process.exit(1)'")

console.log(run.status) // "failed"
```

***

### Chain commands

Pass a full shell expression. Pipes, redirects, and chained commands all work as expected.

```typescript theme={"system"}
const run = await box.exec.command("cd /work && npm install && npm test")

console.log(run.result)
```

***

### Cancel a long-running command

You can cancel a run to abort it. The status becomes `"cancelled"`.

```typescript theme={"system"}
const run = await box.exec.command("sleep 10")
await run.cancel()

console.log(run.status) // "cancelled"
```

***

### Retrieve logs

After a command finishes, call `logs()` to get the full timestamped output for debugging or auditing.

```typescript theme={"system"}
const run = await box.exec.command("npm test")
const logs = await run.logs()

console.log(logs)
// [
//   { timestamp: "2026-02-23T...", level: "info", message: "PASS src/auth.test.ts" },
//   { timestamp: "2026-02-23T...", level: "info", message: "Tests: 12 passed, 12 total" },
// ]
```

***

## Examples

### Install dependencies before a run

Set up the environment with `box.exec.command()`, then hand off to the agent.

```typescript theme={"system"}
import { Agent, Box } from "@upstash/box"

const box = await Box.create({
  runtime: "node",
  agent: { harness: Agent.ClaudeCode, model: "anthropic/claude-opus-4-6", apiKey: process.env.ANTHROPIC_API_KEY },
  git: { token: process.env.GITHUB_TOKEN },
})

await box.git.clone({ repo: "github.com/your-org/your-api" })
await box.exec.command("npm install")

await box.agent.run({
  prompt: "Run the test suite and fix any failing tests",
})
```

### Run a build and extract artifacts

Execute a build command, then download the output.

```typescript theme={"system"}
import { Agent, Box } from "@upstash/box"

const box = await Box.create({ runtime: "node" })

await box.files.upload([
  { path: "./src", destination: "/work/src" },
  { path: "./package.json", destination: "/work/package.json" },
])

await box.exec.command("cd /work && npm install && npm run build")
await box.files.download({ path: "/work/dist" })
await box.delete()
```

### Health-check before handing off

Verify the environment is usable before starting a longer agent task.

```typescript theme={"system"}
import { Agent, Box } from "@upstash/box"

const box = await Box.create({
  runtime: "python",
  agent: { harness: Agent.ClaudeCode, model: "anthropic/claude-opus-4-6", apiKey: process.env.ANTHROPIC_API_KEY },
})

const check = await box.exec.command("python3 --version && pip list")
console.log(check.result)

await box.agent.run({
  prompt: "Write a data pipeline that reads /work/raw.csv, cleans it, and saves /work/clean.parquet",
})
```