Stitch’s DESIGN.md format is now open-source so you can use it across platforms.

Source: Google Date: 2026-04-21 URL: https://blog.google/innovation-and-ai/models-and-research/google-labs/stitch-design-md/

Summary

Google Labs open-sourced the DESIGN.md specification from Stitch, its AI design tool. The format allows designers to export and import design system rules across different platforms and tools, enabling AI agents to understand a project’s design system reasoning — brand guidelines, accessibility constraints, component relationships — and generate interfaces that maintain consistency without guesswork.

Implications

DESIGN.md as an open format is a platform-neutrality play from Google Labs. By open-sourcing the spec before Stitch reaches mainstream adoption, Google is attempting to establish DESIGN.md as the standard interchange format for design system context — the same way OpenAPI became the standard for API description. If it succeeds, Stitch benefits regardless of which AI tool designers use day-to-day, because the format is the durable artifact.

The technical value is real: design systems are notoriously context-heavy and poorly represented by visual assets alone. A structured machine-readable format for design intent (not just visual output) is what would let any AI coding tool generate brand-consistent UI without requiring a custom fine-tune or massive context injection. This is an infrastructure bet on AI-assisted frontend development, not a Stitch feature announcement.

Agentic engineering thread: DESIGN.md is the design-system analog to what CLAUDE.md is for agent instructions or what OpenAPI is for services — structured human intent for machine consumption. If the format gets traction, expect IDE integrations (Cursor, Windsurf, Copilot) to pick it up as a context source for UI generation.

Watch:

• Whether Figma, Framer, or linear design tools adopt DESIGN.md as an export format
• GitHub activity on the DESIGN.md spec repo — adoption speed will be visible
• Whether AI coding tools outside Google (Cursor, v0, Bolt) add native DESIGN.md support