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) β User-space kernel intercepts all syscalls
- Network isolation β Executed code cannot make outbound connections
- Resource limits β CPU, memory, and disk usage are capped
- Ephemeral containers β Destroyed immediately after execution
- Read-only filesystem β No persistent writes between executions
- Code size limits β Source code capped at 1MB
- Timeout enforcement β Hard kill after configured timeout
API Key
Get your API key at sandboxapi.dev or through RapidAPI.
Links
License
MIT