QA: Sub-Agents — Built-in Agent (TanStack AI)

Prerequisites

• Set OPENAI_API_KEY in .env.local (or environment).
• Run npm install --legacy-peer-deps && npm run dev from the built-in-agent/ package directory.
• Demo URL: http://localhost:3000/demos/subagents

Page load

• Page heading "Sub-Agents" is visible.
• Hint text referencing delegate_to_planner / delegate_to_researcher tool names is visible.
• Chat input is visible.

Happy path interaction

• Send: "Plan a 2-day trip to Tokyo with key sights." Verify that one or more delegation cards appear inline in the chat. Each card shows the subagent role ("planner" or "researcher"), a task description, and a "running…" status while in progress.
• After the agent finishes, verify the delegation card(s) transition to "· done" status and display the subagent's output text.

Edge cases worth checking

• Send a message that does not require delegation (e.g. "What is 3 × 7?"). Verify the agent replies without rendering any delegation cards.
• Send a request that triggers both planner and researcher subagents. Verify two separate delegation cards render, one per subagent.