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JavaScriptdeepagentsbackendsLangSmithSandbox
Class●Since v1.8

LangSmithSandbox

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class LangSmithSandbox

Bases

BaseSandbox

Constructors

Properties

Methods

Inherited fromBaseSandbox

Properties

Pid: string
—

Unique identifier for the sandbox backend

Methods

MdownloadFiles→ MaybePromise<FileDownloadResponse[]>
—

Download multiple files from the sandbox.

Medit→ Promise<EditResult>
—

Edit a file by replacing string occurrences.

View source on GitHub
M
execute
→ MaybePromise<ExecuteResponse>
—

Execute a command in the sandbox.

MglobInfo→ Promise<FileInfo[]>
—

Structured glob matching returning FileInfo objects.

MgrepRaw→ Promise<string | GrepMatch[]>
—

Search for a literal text pattern in files using grep.

MlsInfo→ Promise<FileInfo[]>
—

List files and directories in the specified directory (non-recursive).

Mread→ Promise<string>
—

Read file content with line numbers.

MreadRaw→ Promise<FileData>
—

Read file content as raw FileData.

MuploadFiles→ MaybePromise<FileUploadResponse[]>
—

Upload multiple files to the sandbox.

Mwrite→ Promise<WriteResult>
—

Create a new file with content.

constructor
constructor
property
id: string
property
isRunning: boolean
method
close→ Promise<void>
method
downloadFiles→ MaybePromise<FileDownloadResponse[]>
method
edit→ Promise<EditResult>
method
execute→ MaybePromise<ExecuteResponse>
method
globInfo→ Promise<FileInfo[]>
method
grepRaw→ Promise<string | GrepMatch[]>
method
lsInfo→ Promise<FileInfo[]>
method
read→ Promise<string>
method
readRaw→ Promise<FileData>
method
uploadFiles→ MaybePromise<FileUploadResponse[]>
method
write→ Promise<WriteResult>
method
create→ Promise<LangSmithSandbox>

LangSmith Sandbox backend for deepagents.

Extends BaseSandbox to provide command execution and file operations via the LangSmith Sandbox API.

Use the static LangSmithSandbox.create() factory for the simplest setup, or construct directly with an existing Sandbox instance.

Unique identifier for the sandbox backend

Delete this sandbox and mark it as no longer running.

After calling this, isRunning will be false and the sandbox cannot be used again.

Download multiple files from the sandbox. Implementations must support partial success.

Edit a file by replacing string occurrences.

Uses downloadFiles() to read, performs string replacement in TypeScript, then uploadFiles() to write back. No runtime needed on the sandbox host.

Memory-conscious: releases intermediate references early so the GC can reclaim buffers before the next large allocation is made.

Execute a command in the sandbox. This is the only method concrete implementations must provide.

Structured glob matching returning FileInfo objects.

Uses pure POSIX shell (find + stat) via execute() to list all files, then applies glob-to-regex matching in TypeScript. No Python or Node.js needed on the sandbox host.

Glob patterns are matched against paths relative to the search base:

  • * matches any characters except /
  • ** matches any characters including / (recursive)
  • ? matches a single character except /
  • [...] character classes

Search for a literal text pattern in files using grep.

List files and directories in the specified directory (non-recursive).

Uses pure POSIX shell (find + stat) via execute() — works on any Linux including Alpine. No Python or Node.js needed.

Read file content with line numbers.

Uses pure POSIX shell (awk) via execute() — only the requested slice is returned over the wire, making this efficient for large files. Works on any Linux including Alpine (no Python or Node.js needed).

Read file content as raw FileData.

Uses downloadFiles() directly — no runtime needed on the sandbox host.

Upload multiple files to the sandbox. Implementations must support partial success.

Create a new file with content.

Uses downloadFiles() to check existence and uploadFiles() to write. No runtime needed on the sandbox host.

Create and return a new LangSmithSandbox in one step.

This is the recommended way to create a sandbox — no need to import anything from langsmith/experimental/sandbox directly.