Anthropic switched to HTML artifacts from Markdown because they cut rendering...

https://www.slideserve.com/aaron_ward92/what-s-a-practical-html-artifact-layout-for-a-code-review-with-3-findings

Anthropic switched to HTML artifacts from Markdown because they cut rendering costs by 92%, dropping to just $0.08 per 10,000 views. They handle 4.4 million views monthly, and HTML speeds up load times by five times