Building a macOS Agent Workbench with SwiftUI

Across the previous seven articles plus a bonus chapter, we thoroughly explored the inner workings of Open Agent SDK — Agent Loop, the tool system, MCP integration, multi-Agent collaboration, conversation persistence, and multi-LLM support. The bonus chapter even embedded the SDK into a macOS native app, Motive, and ran it live. But Motive was just a backend-swap experiment. The real question is: once you have the SDK, how do you build a complete Agent application from scratch? The SDK gives you