LangSmith Sandboxes

provider: "langsmith"

Sign-up is waitlisted: Sandboxes are a private preview: until LangChain enables them for your organization, the API answers "Sandbox feature is not enabled for this organization". Checked 2026-11-07.

Per second; memory must be 2 to 6 GiB per vCPU; storage $0.000123/GiB-h; 8 LSU ($8) of sandbox usage a month included; Developer plan max 10 sandboxes.

List price per hour

1 vCPU · 2 GB	$0.095
2 vCPU · 4 GB	$0.189
4 vCPU · 8 GB	$0.378
8 vCPU · 16 GB	$0.756
16 vCPU · 32 GB	$1.51
32 vCPU · 128 GB	max 16 vCPU

Source: www.langchain.com, 2026-11-05 (an estimate, not a bill)
Billing: the size you ask for, while it runs
Plan: none needed

Adapter

Supports: Exec + streaming · Files · Pause · Custom image
Max size: 16 vCPU · 96 GB
Routing: Chosen when it's the cheapest fit, if you already have a key
Docs: docs.langchain.com

Measured on real accounts

Real-account check: not run yet; tested against a mock of its API only
Cold start: not measured; no benchmark run yet
Succeeded: not measured; no benchmark run yet
Size you get: not measured; no cost run yet
Billed vs list price: not measured; no cost run yet

Help verify LangSmith Sandboxes

Have a LangSmith Sandboxes account? These run real sandboxes on it, for a few cents at most, and write result files that fill in the blanks above. Results never include your keys. Run them in a clone of the repo and open a pull request with the files: CI checks every file for keys and impossible numbers, and a maintainer reviews each one before it shows here.

terminal

npx @sandboxrouter/sdk check --provider langsmith --save --by YOUR_GITHUB_USERNAME
npx @sandboxrouter/sdk bench --provider langsmith --runs 5 --share --label "your city or cloud region" --by YOUR_GITHUB_USERNAME
npx @sandboxrouter/sdk cost run --provider langsmith --minutes 10 --by YOUR_GITHUB_USERNAME

Real-account check, step by step

Not run on a real account yet; the adapter is tested against a mock of LangSmith Sandboxes's API.

setup

npm i @sandboxrouter/sdk langsmith ws
export LANGSMITH_API_KEY=...

use LangSmith Sandboxes

import { Router } from "@sandboxrouter/sdk";

const router = new Router();
const sbx = await router.create({}, { provider: "langsmith" });
await sbx.exec("uname -a", { onStdout: (c) => process.stdout.write(c) });
await sbx.kill();