{"repo":"CharlieDigital/runjs","free":true,"listed":false,"github":"https://github.com/CharlieDigital/runjs","clone":"git clone https://github.com/CharlieDigital/runjs.git","description":"The only MCP server you need: let your LLM generate and safely execute JavaScript -- including fetch API calls, JSONPath ETL, built-in resiliencey, and secrets management","language":"C#","stars":31,"topics":["ai","llm","mcp","mcp-server"],"license":"MIT","category":"mcp-servers","readme_excerpt":"RunJS - The Only MCP Server You Need This project contains an MCP server that can execute JavaScript safely in an isolated sandbox and return a result from the script. It is equipped with a fetch analogue implemented using System.Net.HttpClient that allows your generated JavaScript to make web requests as well as JSONPath to manipulate the results 😎. A web API is also provided to store secrets securely so that API calls using API keys can be used. With this MCP server, you can basically interact with any REST API. Key Features - Integrated secrets manager to securely store encrypted API keys - Sandboxed JavaScript execution without infrastructure (e.g. deploy a container or serverless function) - Pre-loaded with a fetch analogue for making HTTP requests - Pre-loaded with jsonpath-plus to process JSON payloads - Integrated resilience pipeline (via Polly) for retries on HTTP requests The RunJS MCP server uses Jint -- a C# library that embeds a JavaScript runtime into .NET and allows controlling the execution sandbox by specifying: - Memory limits - Number of statements - Runtime - Depth of calls (recursion) This is extremely powerful as in many cases, you may want to run JavaScript, but doing it safely is challenging because of the nature of JavaScript and generated code. Because the generated JavaScript is run in a C# interpreter, there's no chance of leaking environment variables, no chance of malicious packages, no chance of the JS crashing the server process. Using this me","default_branch":null,"files":null,"tree":[],"storefront":"/r/CharlieDigital","claimed":false,"request_supported":{"post":"https://gitbuyer.com/r/CharlieDigital/runjs/request-supported","requests":0},"note":"indexed from public GitHub; nothing is for sale on this page. Clone it from GitHub. Paid listings live at /search."}