JavaScript Sandbox MCP Server
[](https://mseep.ai/app/garc33-js-sandbox-mcp-server)
# js-sandbox MCP Server
[](https://smithery.ai/server/@garc33/js-sandbox-mcp-server)
A Model Context Protocol server that provides a secure JavaScript execution environment.
<a href="https://glama.ai/mcp/servers/agatnhlgki">
<img width="380" height="200" src="https://glama.ai/mcp/servers/agatnhlgki/badge" alt="JavaScript Sandbox Server MCP server" />
</a>
## Features
### Tools
- `execute_js` - Executes JavaScript code in an isolated environment
- Parameters:
- `code` (required): JavaScript code to execute
- `timeout` (optional): Maximum execution time in milliseconds (100-30000ms)
- `memory` (optional): Memory limit in bytes (1MB-100MB)
- Returns the result of code execution
### Security
- Isolated code execution in a controlled environment
- Configurable execution time and memory limits
- Protection against malicious code
## Development
Install dependencies:
```bash
npm install
```
Build the server:
```bash
npm run build
```
Development mode with auto-rebuild:
```bash
npm run watch
```
## Installation
### Installing via Smithery
To install JavaScript Sandbox Server for Claude Desktop automatically via [Smithery](https://smithery.ai/server/@garc33/js-sandbox-mcp-server):
```bash
npx -y @smithery/cli install @garc33/js-sandbox-mcp-server --client claude
```
To use with Claude Desktop, add the server configuration:
MacOS: `~/Library/Application Support/Claude/claude_desktop_config.json`
Windows: `%APPDATA%/Claude/claude_desktop_config.json`
```json
{
"mcpServers": {
"js-sandbox": {
"command": "/path/to/js-sandbox/build/index.js"
}
}
}
```
### Debugging
Since MCP servers communicate over stdio, debugging can be challenging. We recommend using [MCP Inspector](https://github.com/modelcontextprotocol/inspector), which is available as:
```bash
npm run inspector
```
The Inspector will provide a URL to access debugging tools in your browser.TDQS
Scored across 1 tool
With only one tool, there is no possibility of confusion or overlap between tools. The tool's purpose is clearly defined as executing JavaScript code in isolation, making it distinct by default.
The single tool name 'execute_js' follows a clear verb_noun pattern (execute + js). Since there is only one tool, consistency is inherently perfect with no deviations to assess.
A single tool is too few for a server named 'JavaScript Sandbox MCP Server', which implies broader functionality like evaluating expressions, managing contexts, or handling errors. This minimal set feels thin and under-scoped for the apparent domain.
The tool surface is severely incomplete for a JavaScript sandbox domain. It lacks essential operations such as evaluating expressions, clearing contexts, handling errors, or managing state, which are typical for such environments, leading to significant gaps in functionality.