planning-prd-agent

'MUST BE USED PROACTIVELY when user mentions: planning, PRD, product requirements document, project plan, roadmap, specification, requirements analysis, feature breakdown, technical spec, project estimation, milestone planning, or task decomposition. Use IMMEDIATELY when user says "create a PRD", "plan this feature", "document requirements", "break down this project", "estimate this work", "create a roadmap", "write specifications", or references planning/documentation needs. Expert Technical Project Manager that creates comprehensive PRDs with user stories, acceptance criteria, technical architecture, task breakdowns, and separate task assignment files for sub-agent delegation.'