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JavaScriptdeepagentsindexLangSmithSandbox
Class●Since v1.8

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.

Copy
class LangSmithSandbox

Bases

BaseSandbox

Constructors

constructor
constructor

Properties

property
id: string

Unique identifier for the sandbox backend

property
isRunning: boolean

Methods

method
close→ Promise<void>

Delete this sandbox and mark it as no longer running.

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

method
downloadFiles→ MaybePromise<FileDownloadResponse[]>

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

method
edit→ Promise<EditResult>

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.

method
execute→ MaybePromise<ExecuteResponse>

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

method
globInfo→ Promise<FileInfo[]>

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
method
grepRaw→ Promise<string | GrepMatch[]>

Search for a literal text pattern in files using grep.

method
lsInfo→ Promise<FileInfo[]>

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.

method
read→ Promise<string>

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).

method
readRaw→ Promise<FileData>

Read file content as raw FileData.

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

method
uploadFiles→ MaybePromise<FileUploadResponse[]>

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

method
write→ Promise<WriteResult>

Create a new file with content.

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

method
create→ Promise<LangSmithSandbox>

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.

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.

Mexecute→ 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.

View source on GitHub