copilotkit--copilotkit/showcase/integrations/mastra/qa/agentic-chat-reasoning.md

QA: Agentic Chat (Reasoning) — Mastra

Test Steps

• Navigate to /demos/agentic-chat-reasoning
• Ask a question that could trigger reasoning (e.g. "Explain the Monty Hall problem step by step")
• If the underlying model emits reasoning tokens, verify the ReasoningBlock (data-testid="reasoning-block") renders with an amber banner

Expected Results

• The reasoningMessage slot override is active
• Reasoning content streams italic under an amber "Reasoning" label

Known Limitation

The Mastra weather agent is not guaranteed to emit REASONINGMESSAGE* AG-UI events by default. This demo exists primarily to exercise the slot-override path; on models without reasoning output the ReasoningBlock will simply not render and the chat falls back to normal assistant messages.