2 min read

<generate-html> Web Component

Paul Kinlan

Paul Kinlan

Lead of Chrome DevRel

The <generate-html> Web Component is a LLM-powered custom element that generates and renders interactive HTML or SVG images on the fly using Google Gemini or Chrome's built-in AI.

It uses a double iframe architecture to reduce the ability of any generated code to access your API keys or host page data. The outer iframe exposes a limited API to the host page it mediates all communication with the inner iframe.

Both iframes are sandboxed and both iframes are created via blob URLs so their origin's are null. This means that the inner iframe cannot access the host page or any of the host page or the outer iframe. The outer iframe can't directly access the DOM of the inner iframe other than changing the href source.

If I was to summarise the features of this component I would say it supports:

  • AI-Generated Content: Turns text prompts into interactive web apps (calculators, games) or SVG images.
  • Sandbox: Uses a "Double iframe" architecture to ensure generated code cannot access your API keys or host page data.
  • Multi-Provider: Supports Google Gemini (via API Key) and Chrome Built-in AI (experimental window.LargeLanguageModel).
  • Vanilla JS: Zero framework dependencies. Built with standard Web Components.

Usage

You can install the component directly via npm:

npm install @paulkinlan/generate-html

Then, import the component script and use the tag in your HTML:

<script type="module" src="/src/generate-html.js"></script>

<generate-html
  prompt="Create a snake game"
  api-key="YOUR_GEMINI_API_KEY"
  model="gemini-2.5-flash-latest"
  provider="gemini"
  type="html"
></generate-html>

The demo can be accessed here: https://generate-html-element.paulkinlan-ea.deno.net/

For more details, check out the GitHub repository.

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