A2UI + MCP Apps: Combining the Best of Declarative and Custom Agentic UIs

Originally published on Google Developers Blog - June 17, 2026, by the Google A2UI Team, Ido Salomon, and Liad Yosef.

Three architectural patterns show how to combine A2UI’s declarative rendering with MCP Apps’ custom iframe environments, giving developers a way to build secure, performant, and brand-consistent agentic user experiences.

Why This Matters

Declarative UI and custom iframe-based UI solve different problems — this piece lays out when to reach for each, and how to combine them. Relevant to the A2UI/Storybook integration work I’m involved with.

Read the full article: A2UI + MCP Apps on Google Developers Blog