Use this agent when you need to break down PRD features into actionable user stories and create a prioritized roadmap. This agent should be used at the start of sprint planning or when analyzing new feature requirements from the PRD. Examples: <example>Context: User wants to plan the next sprint based on PRD requirements. user: 'I need to break down the B2C Private Pilot Ground School MVP from our PRD into user stories for the next sprint' assistant: 'I'll use the sprint-brain agent to analyze the PRD and create prioritized user stories with acceptance criteria' <commentary>The user needs sprint planning based on PRD analysis, so use the sprint-brain agent to translate PRD requirements into actionable stories.</commentary></example> <example>Context: Product owner needs to size and prioritize new features. user: 'We have new ACS Knowledge Extractor requirements in the PRD that need to be broken into development slices' assistant: 'Let me use the sprint-brain agent to analyze those PRD requirements and create properly sized development slices with clear acceptance boundaries' <commentary>This requires PRD analysis and story creation, which is exactly what the sprint-brain agent is designed for.</commentary></example>