> ## Documentation Index > Fetch the complete documentation index at: https://docs.instantschema.app/llms.txt > Use this file to discover all available pages before exploring further. # CDN Script > Add InstantSchema to any site with a single script tag # CDN Script The fastest integration — paste one tag into your `` and the hosted loader handles the rest. Schemas are fetched and injected by JavaScript after the page loads. Schemas are **client-injected**, not in the raw HTML source. Google indexes them after executing JavaScript (typically a few seconds after the page loads). For schemas in HTML source, use the [Next.js SDK](/integrations/nextjs) or another server-side method. ## Add the tag Paste this into the `` on every page of your site: ```html theme={null} ``` Replace `YOUR_PROJECT_ID` with the Project ID from your [InstantSchema dashboard](https://app.instantschema.com). ## Attributes | Attribute | Required | Description | | ----------------- | ----------- | ---------------------------------------------------------------- | | `data-project-id` | Yes | Your InstantSchema project ID | | `data-api-url` | No | Override API base URL (default: `https://app.instantschema.com`) | | `async` | Recommended | Non-blocking load; doesn't delay page rendering | ## How it works The loader reads `data-project-id` and `window.location.pathname`, calls `/api/v1/structured-data`, then appends each schema as a `