A2UI + MCP Apps: Combining the best of declarative and custom agentic UIs- Google Developers Blog
6/17/2026 · Google A2UI Team, Ido Salomon, Liad Yosef
What this post added
Introduces architectural patterns for integrating Agent-to-User Interface (A2UI) and Model Context Protocol (MCP) Apps to address the trade-offs between declarative and custom agentic UIs. Pattern 1: Serving A2UI over MCP servers, detailing advantages like bypassing iframe limitations, separation of concerns, enhanced environment portability, simplified security, and accelerated development cycles. It explains static vs. dynamic delivery via MCP Resources and MCP Tool Calls, and contrasts A2UI over MCP with A2UI over A2A architectures. Pattern 2: Running MCP Apps within A2UI components, highlighting benefits such as brand consistency, controlled delegation, specialized capabilities, and secure state alignment.