Show HN: RunJS – a C# MCP server to let LLMs generate and run JavaScript safely

3 CharlieDigital 0 6/19/2025, 12:04:59 PM github.com ↗

RunJS is an MCP server written in C# that let's an LLM generate and execute JavaScript "safely".

It uses the excellent Jint library (https://github.com/sebastienros/jint) which is a .NET JavaScript interpreter that provides a sandboxed runtime for arbitrary JavaScript.

Using Jint also allows for extensibility by allowing JS modules to be loaded as well as providing interop with .NET object instances.

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Show HN: RunJS – a C# MCP server to let LLMs generate and run JavaScript safely

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