Methodology
Language attribute
ia.lang-attribute · 3.6
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Why it matters
The lang attribute tells AI agents what language your content is in, enabling correct text processing, translation, and language-specific understanding.
How to fix it
Add a valid lang attribute to the html element.
-
Set the lang attribute on the html element to the language of the page.
<html lang="en">
Verify
curl -sf https://{domain}/
Expected: The html element has a lang attribute
Run a new scan for this checkpoint:
isagentready results {domain} --checkpoint ia.lang-attribute
Details Mapping, lifecycle and references
- AR mapping
- No AR practice
- Evidence source
- MDN lang attribute
- Score role
- Core
- Introduced
- 2026-08-24
- Methodology version
- 2026-10-22