Generate a structured milestone summary for team onboarding and project review. Reads completed milestone artifacts (ROADMAP, REQUIREMENTS, CONTEXT, SUMMARY, VERIFICATION files) and produces a human-friendly overview of what was built, how, and why.

Purpose: Enable new team members to understand a completed project by reading one document and asking follow-up questions. Output: MILESTONE_SUMMARY written to .planning/reports/, presented inline, optional interactive Q&A.

<execution_context> @~/.claude/gsd-core/workflows/milestone-summary.md </execution_context>

**Project files:** - `.planning/ROADMAP.md` - `.planning/PROJECT.md` - `.planning/STATE.md` - `.planning/RETROSPECTIVE.md` - `.planning/milestones/v{version}-ROADMAP.md` (if archived) - `.planning/milestones/v{version}-REQUIREMENTS.md` (if archived) - `.planning/phases/*-*/` (SUMMARY.md, VERIFICATION.md, CONTEXT.md, RESEARCH.md)

User input:

• Version: $ARGUMENTS (optional — defaults to current/latest milestone)

Execute end-to-end.

<success_criteria>

• Milestone version resolved (from args, STATE.md, or archive scan)
• All available artifacts read (ROADMAP, REQUIREMENTS, CONTEXT, SUMMARY, VERIFICATION, RESEARCH, RETROSPECTIVE)
• Summary document written to .planning/reports/MILESTONE_SUMMARY-v{version}.md
• All 7 sections generated (Overview, Architecture, Phases, Decisions, Requirements, Tech Debt, Getting Started)
• Summary presented inline to user
• Interactive Q&A offered
• STATE.md updated </success_criteria>