Content Without JavaScript

Compares the content in your raw HTML against the JavaScript-rendered DOM and flags pages where significant main content only exists after JS runs. Many AI agents and crawlers read raw HTML without executing JavaScript, so anything injected client-side is invisible to them.

Rule ID	ax/content-without-js
Category	Agent Experience
Scope	Per page
Severity	info
Weight	2/10

What it checks

The rule needs both versions of the page:

• Raw HTML: the initial server response, before any JavaScript runs (what a no-JS agent sees).
• Rendered DOM: the page after the cloud render service executes JavaScript in a real browser.

It extracts the visible text from each with the same pipeline and compares word counts. A page is flagged (info) only when all of the following hold:

• the rendered page has at least 200 words of content,
• at least 100 words exist only after JavaScript runs, and
• the raw HTML covers 60% or less of the rendered content.

Server-rendered (SSR/SSG) pages, where the raw HTML already carries the content, pass. Single-page-app shells that ship a near-empty <div id="root"> and hydrate everything client-side are flagged.

Why it matters

A growing share of traffic comes from agents that fetch raw HTML and never run JavaScript: LLM crawlers, answer engines, link unfurlers, and many automation tools. Content that only appears post-hydration is invisible to all of them: your page may look complete in a browser yet read as empty to an agent. Putting the core content in the initial HTML makes the page legible to both.

Solution

Server-render or pre-render your primary content so it is present in the initial HTML:

• Use SSR or static generation (SSG) for the main content of each page.
• Keep purely interactive enhancements client-side: only the core content an agent needs to understand the page has to be in the raw HTML.
• Verify by fetching the page without JavaScript (e.g. curl the URL) and confirming the main content is present.

# What a no-JS agent sees — the main content should already be here
curl -s https://example.com/page | grep -i "your main heading"