Anthropic switched to HTML artifacts for internal planning, code reviews,...

https://blogfreely.net/samuel-wang09/how-much-does-an-html-artifact-cost-on-opus-4-7-is-it-really-0-08

Anthropic switched to HTML artifacts for internal planning, code reviews, design systems, and reports because they load 5 times faster than Markdown files. This speed boost helps the team stay efficient and responsive when reviewing detailed docs