🎙️ How I AI: HTML is the new Markdown: How Anthropic engineers are building with Claude Code

2026-05-18 · Source: Lenny's Newsletter · Field: Technology & Digital — Artificial Intelligence & Machine Learning, Software Development & Engineering, Emerging Technologies & Innovation · Depth: Advanced, extended

Summary

Anthropic engineer Thariq Shihipar advocates for HTML as a superior communication format for AI agents, replacing Markdown for project planning and specifications. Recorded live at Anthropic's Code with Claude event, Shihipar demonstrates how HTML artifacts enable richer expression through interactive elements, visual mockups, and scrollable sections, improving engagement with lengthy AI-generated plans. He highlights that engineers are evolving into "compute allocators," focusing on defining project boundaries and staying synchronized with agents, rather than solely writing code. The discussion covers building custom, disposable UIs for editing specific plan sections, creating living design systems in HTML, and the importance of simple, trusting prompts for Claude. Shihipar notes that only about 1% of generated tokens become production code, with the majority used for internal tools and rich interfaces.

Key takeaway

For AI Architects and AI Product Managers designing and overseeing AI-driven development, adopting HTML for project specifications and design systems is crucial. This shift from Markdown to HTML allows for more interactive and visually engaging plans, improving your ability to stay in sync with AI agents and refine outputs. Focus on defining clear project boundaries and leveraging AI to create custom interfaces for complex tasks, rather than getting bogged down in manual code writing or editing.

Key insights

HTML offers richer, more interactive communication with AI agents than Markdown, enhancing engagement and product quality.

Principles

• HTML enables richer AI communication.
• Engineers allocate compute, not just code.
• Simple, trusting prompts yield better AI results.

Method

Use HTML for AI-generated project plans, interactive specs, and living design systems. Create disposable micro-UIs for specific editing tasks, and employ simple, open-ended prompts to guide the AI.

In practice

• Generate interactive HTML project plans.
• Build custom UIs for plan editing.
• Maintain HTML-based design systems.

Topics

• HTML-AI Interaction
• Claude Code
• Compute Allocation
• HTML Design Systems
• Disposable Micro-Apps

Best for: AI Architect, AI Product Manager, AI Engineer, Machine Learning Engineer, Director of AI/ML

Related on AIssential

• HTML is the new Markdown: How Anthropic engineers are building with Claude Code | Thariq Shihipar — HTML offers a richer, more engaging communication medium for human-AI interaction than Markdown, improving collaboration and output quality.
• Anthropic CEO: “ I have engineers within anthropic who don’t write any code, they just let Claude write the code and they edit it and look it over” — AI code generation shifts developer focus from writing to architectural design, review, and quality assurance.
• Using Claude Code: The unreasonable effectiveness of HTML — HTML offers richer, more readable, and interactive outputs for AI agents compared to Markdown.
• Why this Claude Code engineer uses HTML files as AI specs | Thariq Shihipar (Anthropic) — HTML is replacing Markdown as the preferred medium for human-AI interaction due to its richer, more engaging visual capabilities.
• According to Anthropic’s Engineer, HTML is the New Markdown for AI Agents — HTML transforms static AI outputs into interactive, reusable interfaces, enabling human action.
• Markdown is for Thinking. HTML is for Showing. — AI output needs a two-stage workflow, distinguishing between raw ideation and polished presentation.

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Editorial summary, takeaway, and curation by AIssential. Original article published by Lenny's Newsletter.