---
title: Sessions
description: Create shell sessions with independent working directories and environment variables within a sandbox.
image: https://edgetunnel-b2h.pages.dev/dev-products-preview.png
---

> Documentation Index  
> Fetch the complete documentation index at: https://edgetunnel-b2h.pages.dev/sandbox/llms.txt  
> Use this file to discover all available pages before exploring further. 

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# Sessions

Create shell sessions within a sandbox. Each session maintains its own shell state, environment variables, and working directory, while sharing the sandbox filesystem and process space. For more information, refer to [Session management](https://edgetunnel-b2h.pages.dev/sandbox/concepts/sessions/).

Note

By default, for backwards compatibility, every sandbox has a default session that maintains shell state. It is recommended to set `enableDefaultSession` to `false` on `getSandbox()` so operations without an explicit `sessionId` run in isolation. Create additional sessions for separate workflows inside the same user workspace, such as development and runtime processes using the `createSession()` method. Use separate sandboxes for separate users. For sandbox-level operations like creating containers or destroying the entire sandbox, refer to the [Lifecycle API](https://edgetunnel-b2h.pages.dev/sandbox/api/lifecycle/).

## Methods

### `createSession()`

Create a new shell session.

**TypeScript**

```ts
const session = await sandbox.createSession(options?: SessionOptions): Promise<ExecutionSession>
```

**Parameters**:

* `options` (optional):  
  * `id` \- Custom session ID (auto-generated if not provided)
  * `env` \- Environment variables for this session: `Record<string, string | undefined>`
  * `cwd` \- Working directory (default: `"/workspace"`)
  * `commandTimeoutMs` \- Maximum time in milliseconds that any command in this session can run before timing out. Individual commands can override this with the `timeout` option on `exec()`.

**Returns**: `Promise<ExecutionSession>` with all sandbox methods bound to this session

* [  JavaScript ](#tab-panel-11047)
* [  TypeScript ](#tab-panel-11048)

**JavaScript**

```js
// Separate workflow environments
const prodSession = await sandbox.createSession({
  id: "prod",
  env: { NODE_ENV: "production", API_URL: "https://api.example.com" },
  cwd: "/workspace/prod",
});


const testSession = await sandbox.createSession({
  id: "test",
  env: {
    NODE_ENV: "test",
    API_URL: "http://localhost:3000",
    DEBUG_MODE: undefined, // Skipped, not set in this session
  },
  cwd: "/workspace/test",
});


// Run in parallel
const [prodResult, testResult] = await Promise.all([
  prodSession.exec("npm run build"),
  testSession.exec("npm run build"),
]);


// Session with a default command timeout
const session = await sandbox.createSession({
  commandTimeoutMs: 5000, // 5s timeout for all commands
});


await session.exec("sleep 10"); // Times out after 5s


// Per-command timeout overrides session-level timeout
await session.exec("sleep 10", { timeout: 3000 }); // Times out after 3s
```

**TypeScript**

```ts
// Separate workflow environments
const prodSession = await sandbox.createSession({
  id: 'prod',
  env: { NODE_ENV: 'production', API_URL: 'https://api.example.com' },
  cwd: '/workspace/prod'
});


const testSession = await sandbox.createSession({
  id: 'test',
  env: {
    NODE_ENV: 'test',
    API_URL: 'http://localhost:3000',
    DEBUG_MODE: undefined // Skipped, not set in this session
  },
  cwd: '/workspace/test'
});


// Run in parallel
const [prodResult, testResult] = await Promise.all([
  prodSession.exec('npm run build'),
  testSession.exec('npm run build')
]);


// Session with a default command timeout
const session = await sandbox.createSession({
  commandTimeoutMs: 5000 // 5s timeout for all commands
});


await session.exec('sleep 10'); // Times out after 5s


// Per-command timeout overrides session-level timeout
await session.exec('sleep 10', { timeout: 3000 }); // Times out after 3s
```

### `getSession()`

Retrieve an existing session by ID.

**TypeScript**

```ts
const session = await sandbox.getSession(sessionId: string): Promise<ExecutionSession>
```

**Parameters**:

* `sessionId` \- ID of an existing session

**Returns**: `Promise<ExecutionSession>` bound to the specified session

* [  JavaScript ](#tab-panel-11041)
* [  TypeScript ](#tab-panel-11042)

**JavaScript**

```js
// First request - create a task-specific session
const session = await sandbox.createSession({ id: "build" });
await session.exec("git clone https://github.com/user/repo.git");
await session.exec("cd repo && npm install");


// Second request - resume session (environment and cwd preserved)
const session = await sandbox.getSession("build");
const result = await session.exec("cd repo && npm run build");
```

**TypeScript**

```ts
// First request - create a task-specific session
const session = await sandbox.createSession({ id: 'build' });
await session.exec('git clone https://github.com/user/repo.git');
await session.exec('cd repo && npm install');


// Second request - resume session (environment and cwd preserved)
const session = await sandbox.getSession('build');
const result = await session.exec('cd repo && npm run build');
```

---

### `deleteSession()`

Delete a session and clean up its resources.

**TypeScript**

```ts
const result = await sandbox.deleteSession(sessionId: string): Promise<SessionDeleteResult>
```

**Parameters**:

* `sessionId` \- ID of the session to delete (cannot be `"default"`)

**Returns**: `Promise<SessionDeleteResult>` containing:

* `success` \- Whether deletion succeeded
* `sessionId` \- ID of the deleted session
* `timestamp` \- Deletion timestamp

* [  JavaScript ](#tab-panel-11043)
* [  TypeScript ](#tab-panel-11044)

**JavaScript**

```js
// Create a temporary session for a specific task
const tempSession = await sandbox.createSession({ id: "temp-task" });


try {
  await tempSession.exec("npm run heavy-task");
} finally {
  // Clean up the session when done
  await sandbox.deleteSession("temp-task");
}
```

**TypeScript**

```ts
// Create a temporary session for a specific task
const tempSession = await sandbox.createSession({ id: 'temp-task' });


try {
  await tempSession.exec('npm run heavy-task');
} finally {
  // Clean up the session when done
  await sandbox.deleteSession('temp-task');
}
```

Warning

Deleting a session immediately terminates all running commands. The default session cannot be deleted.

---

### `setEnvVars()`

Set environment variables in the sandbox.

**TypeScript**

```ts
await sandbox.setEnvVars(envVars: Record<string, string | undefined>): Promise<void>
```

**Parameters**:

* `envVars` \- Key-value pairs of environment variables to set or unset  
  * `string` values: Set the environment variable
  * `undefined` or `null` values: Unset the environment variable

Warning

Call `setEnvVars()` **before** any other sandbox operations to ensure environment variables are available from the start.

* [  JavaScript ](#tab-panel-11045)
* [  TypeScript ](#tab-panel-11046)

**JavaScript**

```js
const sandbox = getSandbox(env.Sandbox, "user-123");


// Set environment variables first
await sandbox.setEnvVars({
  API_KEY: env.OPENAI_API_KEY,
  DATABASE_URL: env.DATABASE_URL,
  NODE_ENV: "production",
  OLD_TOKEN: undefined, // Unsets OLD_TOKEN if previously set
});


// Now commands can access these variables
await sandbox.exec("python script.py");
```

**TypeScript**

```ts
const sandbox = getSandbox(env.Sandbox, 'user-123');


// Set environment variables first
await sandbox.setEnvVars({
  API_KEY: env.OPENAI_API_KEY,
  DATABASE_URL: env.DATABASE_URL,
  NODE_ENV: 'production',
  OLD_TOKEN: undefined // Unsets OLD_TOKEN if previously set
});


// Now commands can access these variables
await sandbox.exec('python script.py');
```

---

## ExecutionSession methods

The `ExecutionSession` object has all sandbox methods bound to the specific session:

| Category             | Methods                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
| -------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Commands**         | [exec()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#exec), [execStream()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#execstream)                                                                                                                                                                                                                                                                                                                                                                                                           |
| **Processes**        | [startProcess()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#startprocess), [listProcesses()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#listprocesses), [killProcess()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#killprocess), [killAllProcesses()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#killallprocesses), [getProcessLogs()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#getprocesslogs), [streamProcessLogs()](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/#streamprocesslogs) |
| **Files**            | [writeFile()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#writefile), [readFile()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#readfile), [mkdir()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#mkdir), [deleteFile()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#deletefile), [renameFile()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#renamefile), [moveFile()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#movefile), [gitCheckout()](https://edgetunnel-b2h.pages.dev/sandbox/api/files/#gitcheckout)  |
| **Environment**      | [setEnvVars()](https://edgetunnel-b2h.pages.dev/sandbox/api/sessions/#setenvvars)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| **Terminal**         | [terminal()](https://edgetunnel-b2h.pages.dev/sandbox/api/terminal/#terminal)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| **Code Interpreter** | [createCodeContext()](https://edgetunnel-b2h.pages.dev/sandbox/api/interpreter/#createcodecontext), [runCode()](https://edgetunnel-b2h.pages.dev/sandbox/api/interpreter/#runcode), [listCodeContexts()](https://edgetunnel-b2h.pages.dev/sandbox/api/interpreter/#listcodecontexts), [deleteCodeContext()](https://edgetunnel-b2h.pages.dev/sandbox/api/interpreter/#deletecodecontext)                                                                                                                                                                         |

## Related resources

* [Session management concept](https://edgetunnel-b2h.pages.dev/sandbox/concepts/sessions/) \- How sessions work
* [Commands API](https://edgetunnel-b2h.pages.dev/sandbox/api/commands/) \- Execute commands

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