useChat from @ai-sdk/react which expects AI SDK formatted events (text-delta, etc.)toAISdkFormat(workflowStream, { from: 'workflow' }) only emits workflow metadata (data-workflow parts), not the actual text content from agent stepsworkflow-step-output events that contain the text from agent steps, but toAISdkFormat with from: 'workflow' doesn't extract this text—it only provides workflow structure metadata.workflowRoute() exists in @mastra/ai-sdk, but it's designed for Mastra's built-in Hono server, not Fastify.workflow-step-output eventsworkflowRoute() handler somehow with Fastify