QA: Sub-Agents — Spring AI

Prerequisites

• Demo is deployed and accessible
• Agent backend is healthy (check /api/health)
• OPENAI_API_KEY is set on the Spring backend

Architecture under test

• Spring's SubagentsController runs a per-request supervisor agent that exposes three tools — research_agent, writing_agent, critique_agent — each backed by its own ChatClient call with a dedicated system prompt (research vs. writing vs. critique).
• Every tool invocation appends a Delegation entry { id, sub_agent, task, status, result } to state.delegations and emits a STATE_SNAPSHOT event, so the UI's live "delegation log" panel grows entry-by-entry while the supervisor works.

Test Steps

1. Page load

• Navigate to /demos/subagents.
• Verify the delegation log card renders (data-testid="delegation-log").
• Verify it shows the empty-state message ("Ask the supervisor to complete a task...").
• Verify data-testid="delegation-count" reads "0 calls".
• Verify the chat panel is visible on the right with the "Give the supervisor a task..." placeholder.

2. Single delegation

• Send: "Research the basics of magnesium supplementation. Just one delegation, no writing or critique."
• While the supervisor is running, verify data-testid="supervisor-running" is visible.
• Verify exactly one data-testid="delegation-entry" appears with sub-agent label "Research" and status "completed".
• Verify data-testid="delegation-count" reads "1 calls".

3. Full pipeline

• Click the "Write a blog post" suggestion (or send the equivalent message manually).
• Watch the delegation log grow in real time:
  • First entry: Research (sub_agent = research_agent)
  • Second entry: Writing (sub_agent = writing_agent) — should contain a polished one-paragraph draft.
  • Third entry: Critique (sub_agent = critique_agent) — should contain 2–3 actionable critiques.
• Verify each entry's "Task" line shows what the supervisor passed to that sub-agent.
• Verify final supervisor message is concise (a short summary, not a replay of all three sub-agent outputs).

4. Live snapshot ordering

• Verify the entries appear incrementally — the writing entry should not show up at the same time as the research entry; if it does, the backend is batching state snapshots.

5. Multi-turn

• After the pipeline completes, send: "Now do the same for the benefits of cold exposure training."
• Verify three more entries are appended (count = 6).
• Verify older entries remain visible (delegation log is append-only within a thread).

6. Error handling

• Send an empty message — UI should handle gracefully.
• If a sub-agent fails (transient OpenAI error), verify the entry's status field reads "failed" and its result starts with "Sub-agent failed:".
• No console errors during normal usage.

Expected Results

• Page loads within 3 seconds.
• First delegation entry appears within 10 seconds of sending the message; subsequent entries appear as each sub-agent ChatClient call completes.
• "Supervisor running" indicator clears as soon as the run finishes.
• Final delegation count matches the number of sub-agent calls the supervisor made (typically 1 or 3).
• No UI errors, no broken layout, no overlap between log and chat panes.