run_js_ephemeral
Execute JavaScript code in temporary containers with optional npm dependencies, automatically cleaning up after execution for secure one-time script runs.
Instructions
Run a JavaScript snippet in a temporary disposable container with optional npm dependencies, then automatically clean up. The code must be valid ESModules (import/export syntax). Ideal for simple one-shot executions without maintaining a sandbox or managing cleanup manually. When reading and writing from the Node.js processes, you always need to read from and write to the "./files" directory to ensure persistence on the mounted volume. This includes images (e.g., PNG, JPEG) and other files (e.g., text, JSON, binaries).
Example:
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| code | Yes | JavaScript code to run inside the ephemeral container. | |
| dependencies | No | A list of npm dependencies to install before running the code. Each item must have a `name` (package) and `version` (range). If none, returns an empty array. | |
| image | No | Docker image to use for ephemeral execution. e.g. - **node:lts-slim**: Node.js LTS version, slim variant. (Lightweight and fast for JavaScript execution tasks.) - **mcr.microsoft.com/playwright:v1.52.0-noble**: Playwright image for browser automation. (Preconfigured for running Playwright scripts.) - **alfonsograziano/node-chartjs-canvas:latest**: Chart.js image for chart generation and mermaid charts generation. ('Preconfigured for generating charts with chartjs-node-canvas and Mermaid. Minimal Mermaid example: import fs from "fs"; import { run } from "@mermaid-js/mermaid-cli"; fs.writeFileSync("./files/diagram.mmd", "graph LR; A-->B;", "utf8"); await run("./files/diagram.mmd", "./files/diagram.svg");) | node:lts-slim |