OpenSandbox MCP Sandbox Server

Overview

OpenSandbox MCP Server exposes the OpenSandbox Python SDK as MCP tools for Claude Code, Cursor, and other MCP-capable clients. It provides focused sandbox lifecycle management, command execution, and text file operations.

Installation & Startup

Source

cd sdks/mcp/sandbox/python
uv sync
uv run opensandbox-mcp

Package

pip install opensandbox-mcp
opensandbox-mcp

Configuration

Environment variables:

• OPEN_SANDBOX_API_KEY
• OPEN_SANDBOX_DOMAIN

CLI overrides:

opensandbox-mcp --api-key ... --domain ... --protocol https

Config fields:

• api_key: OpenSandbox API key for authentication.
• domain: OpenSandbox API domain, for example api.opensandbox.io.
• protocol: http or https for API requests.
• request_timeout_seconds: HTTP request timeout in seconds.
• transport: stdio by default, or streamable-http.

Streamable HTTP

opensandbox-mcp \
  --transport streamable-http

Integrations

Claude Code stdio

claude mcp add opensandbox-sandbox --transport stdio -- \
  opensandbox-mcp --api-key "$OPEN_SANDBOX_API_KEY" --domain "$OPEN_SANDBOX_DOMAIN"

Claude Code http

claude mcp add opensandbox-sandbox --transport http http://localhost:8000/mcp

Cursor stdio

{
  "mcpServers": {
    "opensandbox-sandbox": {
      "command": "opensandbox-mcp",
      "args": [
        "--api-key",
        "${OPEN_SANDBOX_API_KEY}",
        "--domain",
        "${OPEN_SANDBOX_DOMAIN}"
      ]
    }
  }
}

Cursor http

{
  "mcpServers": {
    "opensandbox-sandbox": {
      "url": "http://localhost:8000/mcp"
    }
  }
}

Tools

INFO

• Tools that interact with a sandbox use an ID registered by sandbox_create or sandbox_connect. sandbox_list lists server-side sandboxes without an existing local sandbox registration.
• file_read/file_write are text-only; use encoding and range_header for large files.

The MCP server exposes the tool set below, not the complete Python SDK. It does not currently register tools for Client Pool, pool tracing, snapshots, templates, Credential Vault, or stable remote diagnostic logs/events. Use the SDK guides or CLI for those workflows where supported.

Sandbox

• sandbox_create: create a new sandbox and register it locally
• sandbox_connect: attach to an existing sandbox and register it locally
• sandbox_kill: terminate a sandbox by ID
• sandbox_get_info: fetch sandbox info by ID
• sandbox_list: list sandboxes with optional filter object
• sandbox_renew: extend sandbox expiration
• sandbox_healthcheck: check if sandbox is healthy
• sandbox_get_metrics: get resource metrics
• sandbox_get_endpoint: get network endpoint for a port

Command Execution

• command_run: run a command inside a sandbox
• command_interrupt: interrupt a running command

Filesystem

• file_read: read a text file
• file_write: write a text file
• file_delete: delete files
• file_search: search for files by glob
• file_create_directories: create directories
• file_delete_directories: delete directories
• file_move: move/rename files or directories
• file_replace_contents: replace file content

Minimal Workflow

1. sandbox_create -> keep the sandbox_id.
2. file_write code or assets into the sandbox.
3. command_run to execute, install dependencies, or start a service.
4. sandbox_get_endpoint if you expose a port.
5. sandbox_kill when finished.

Usage Examples

Here are some examples of what you can ask an LLM to do:

• "Create a Python sandbox and run a quick health command."
• "Write a Python script into the sandbox and run it."
• "Download a GitHub repo, install dependencies, and run its tests."
• "Generate a CSV file with fake sales data and run a simple summary script."
• "Start a tiny web server on port 8000 and return the public URL."
• "Build a minimal REST API (hello + health) and expose it on port 8000."
• "Create a tar.gz of /app and report the file size."
• "Build a simple Snake game and return the web endpoint where it can be accessed."