In vibe coding, AI loves to output long, smelly Markdown documents — plans, summaries, PR descriptions, execution reports. Markdown is indeed concise, token-efficient, and version-control friendly. But its problem is this: it’s better at generating text than at helping humans review complex decisions.
When agents start taking on harder engineering tasks, what we need is not longer Markdown, but higher information density — output interfaces that are more visual and easier for humans to participate in and control. HTML artifacts happen to offer exactly that.
Markdown is hard for humans to actually sit down and read. And AI is not human.
1. Why HTML expresses information better
HTML usually conveys richer information than Markdown. Sure, AI is now strong enough to draw flowcharts with ASCII characters — but that’s like putting an extra constraint on the AI, while HTML gives it much more freedom to express things to humans.
- Tables: HTML can render beautiful tables. Markdown can technically do tables too, but they’re painful to maintain.
- Flowcharts — this one needs no explanation.
- You can adjust parameters on the interface in real time and generate prompts from them. There’s a story in Steve Jobs’ biography about an engineer who wrote a parameter-tuning program so Jobs could tweak things to exactly the style he liked.
- Compared with Markdown, HTML is simply easier for people to actually read.
2. Downsides of expressing things in HTML
Richer, more readable — but there are a few catches:
- Generating HTML is slower than Markdown. Anthropic engineer Thariq says it’s roughly 3–4x slower.
- It also costs more tokens than Markdown.