Runno Code Sandbox
About
The @runno/mcp server provides a run_code tool that AI assistants can use to execute code snippets in various programming languages. It leverages the @runno/sandbox package, which uses WebAssembly to create isolated environments for code execution. The result of the code executio
Details
- Author
- taybenlor
- Downloads
- 415
- Categories
- Other
Jump to
- Runs code in the browser using WebAssembly and WASI.
- Provides a sandboxed, in-memory file system.
- Supports multiple runtimes: Python, Ruby, QuickJS, SQLite, Clang, Clang++, PHP-CGI.
- Offers both web components (@runno/runtime) and a headless WASI runtime (@runno/wasi).
- Code executes in a Web Worker with terminal emulation via XTerm.js.
- No server-side execution required—all processing happens on the client.
Setting up with Highlight
This MCP is not yet compatible with Highlight’s one-click setup. However, you can still use it with Highlight by following these steps:
- Download and install Highlight from highlightai.com/download
- Navigate to the plugins tab and select "Add Custom Plugin"
-
Configure the plugin with the settings below
Plugin Name
Runno Code SandboxCommand (node, npx, python, etc.)Please refer to the README for specific instructions on how to obtain API keys or other required environment variables.
- Enable "Start Automatically" if you want the plugin to start when Highlight launches
From the repository
Install the @runno/runtime npm package, import it in your entrypoint file, and set the HTTP headers Cross-Origin-Opener-Policy: same-origin and Cross-Origin-Embedder-Policy: require-corp to create a cross-origin isolated context. Then use the <runno-run> element with a supported runtime (e.g., runtime="python") and your code as its content. For running WASI binaries directly, use <runno-wasi>.
Claude Desktop / Cursor
Paste into your MCP client config file to install this server.
{
"mcpServers": {
"runno code sandbox": {
"runno": {
"command": "/usr/local/bin/npx",
"args": [
"@runno/mcp"
]
}
}
}
}McpServers
{
"runno": {
"command": "/usr/local/bin/npx",
"args": [
"@runno/mcp"
]
}
}Runno
Runno helps you make runnable code examples that can be embedded in web pages.
This project is powered by WASI the Web Assembly System
Interface. It provides a standard way for programs to interact with an
operating system. By emulating this interface, we can provide a fake file system
and operating system, all running within the browser. Then we can run
programming languages in the browser, without modification.
This is very handy for programming education it means:
- No need for newbies to install complex programming tools to run code
- Programming examples can be made runnable in the browser with no server
- Simple programs can be tested for correctness inside a sandbox on the user's machine
Runno also ships its own WASI runtime (@runno/wasi) which is used to power
Runno under the hood. It can be used independently to run WASI binaries in the
browser.
Two parts to Runno
There are two main parts to runno:
1. @runno/runtime - web components and headless tools for running code examples in the browser.
2. @runno/wasi - a sandboxed implementation of WASI made for the browser that works on the server.
The @runno/runtime is built on top of the primitives provided by @runno/wasi.
Sign in to leave a review
Use Google, GitHub, or an email account so ratings stay tied to real people.
No reviews posted yet.
