Adding Multi-Agent Orchestration to a Vercel AI SDK App

I hit a wall recently. I had a working AI SDK app -- streamText, useChat, the whole thing -- and then I needed it to do something that a single agent can't: research a topic with one agent, then hand that research to a second agent for writing. You can do this manually. Glue two generateText calls together, pass context around, handle the error cases. But once you want a coordinator that figures out which tasks to run in what order, or three agents sharing state, you're writing orchestration in...