ModalSandbox integration | LangChain English

Modal provides serverless container infrastructure with GPU support. See the Modal docs for signup, authentication, and platform details.

Installation

pip

pip install langchain-modal

uv add langchain-modal

Create a sandbox backend

In Python, you create the sandbox using the provider SDK, then wrap it with the deepagents backend.

import modal

from langchain_modal import ModalSandbox

app = modal.App.lookup("your-app")
modal_sandbox = modal.Sandbox.create(app=app)
backend = ModalSandbox(sandbox=modal_sandbox)

result = backend.execute("echo hello")
print(result.output)

Use with Deep Agents

import modal
from langchain_anthropic import ChatAnthropic

from deepagents import create_deep_agent
from langchain_modal import ModalSandbox

app = modal.App.lookup("your-app")
modal_sandbox = modal.Sandbox.create(app=app)
backend = ModalSandbox(sandbox=modal_sandbox)

agent = create_deep_agent(
    model=ChatAnthropic(model="claude-sonnet-4-6"),
    system_prompt="You are a coding assistant with sandbox access.",
    backend=backend,
)

result = agent.invoke(
    {"messages": [{"role": "user", "content": "Install numpy and calculate pi"}]}
)

Cleanup

You are responsible for managing the sandbox lifecycle via Modal. When you are done, terminate the sandbox.