SandboxAPI

SandboxAPI MCP Server

  

Give your AI agent the ability to execute code in 8 programming languages, safely.

SandboxAPI MCP Server connects any MCP-compatible AI client (Claude, Cursor, VS Code, Windsurf, etc.) to secure code execution. Every execution runs inside a gVisor-sandboxed Docker container with no network access, strict resource limits, and ephemeral filesystems.

Quick Start

Option 1: Remote Server (No Setup)

Connect directly to the hosted endpoint. No local installation required.

Claude Desktop (claude_desktop_config.json):

{
  "mcpServers": {
    "sandboxapi": {
      "url": "https://mcp.sandboxapi.dev/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

VS Code (.vscode/mcp.json):

{
  "servers": {
    "sandboxapi": {
      "url": "https://mcp.sandboxapi.dev/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Cursor (~/.cursor/mcp.json):

{
  "mcpServers": {
    "sandboxapi": {
      "url": "https://mcp.sandboxapi.dev/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Option 2: Docker

docker run -d \
  -p 8081:8081 \
  -e SANDBOXAPI_API_KEY=your_sandboxapi_key \
  -e MCP_API_KEY=your_mcp_auth_key \
  sandboxapi/mcp:latest

Then point your client to http://localhost:8081/mcp.

Option 3: Build from Source

git clone https://github.com/sandboxapi/sandboxapi-mcp.git
cd sandboxapi-mcp
go build -o sandboxapi-mcp .

export SANDBOXAPI_API_KEY=your_key
export MCP_API_KEY=optional_auth_key
./sandboxapi-mcp

Available Tools

execute_code

Execute code in a sandboxed container.

| Parameter | Type | Required | Description | |------------|--------|----------|-------------| | language | string | Yes | python3, javascript, typescript, bash, java, cpp, c, go | | code | string | Yes | Source code to execute (max 1MB) | | timeout | number | No | Timeout in seconds (default: 10, max: 300) | | stdin | string | No | Standard input to pass to the program |

execute_batch

Execute multiple code snippets. Each runs in its own isolated sandbox.

| Parameter | Type | Required | Description | |--------------|-------|----------|-------------| | executions | array | Yes | Array of {language, code, timeout?, stdin?} objects |

list_languages

List all supported programming languages with versions and example code. No parameters.

Supported Languages

| Language | Version | Aliases | |------------|----------|---------| | Python | 3.12 | python3, python, py | | JavaScript | Node 22 | javascript, js, node | | TypeScript | 5.4 | typescript, ts | | Go | 1.22 | go, golang | | Java | 21 | java, jdk | | C++ | GCC 14 | cpp, c++ | | C | GCC 14 | c, gcc | | Bash | 5.2 | bash, sh, shell |

Environment Variables

| Variable | Required | Description | |---------------------|----------|-------------| | SANDBOXAPI_API_KEY | Yes | API key for the SandboxAPI backend | | MCP_API_KEY | No | Auth key for the MCP endpoint (omit for open access) | | MCP_PORT | No | Port to listen on (default: 8081) | | SANDBOXAPI_URL | No | API base URL (default: https://api.sandboxapi.dev) |

Security

Every code execution is isolated with defense-in-depth:

• gVisor (runsc) — User-space kernel intercepts all syscalls
• Network isolation — Executed code cannot make outbound connections
• Resource limits — CPU, memory, and disk usage are capped
• Ephemeral containers — Destroyed immediately after execution
• Read-only filesystem — No persistent writes between executions
• Code size limits — Source code capped at 1MB
• Timeout enforcement — Hard kill after configured timeout

API Key

Get your API key at sandboxapi.dev or through RapidAPI.

Links

• Website
• Playground
• RapidAPI Listing
• MCP Specification

License

MIT