Milestone
This skill writes:
production/milestone.mdproduction/milestone-xx-name/
Phase 1: Validate Inputs
Fail if any of these are missing:
design/gdd/game.mddesign/gdd/systems-index.mddesign/art/art-direction.md
Also stop if no system GDDs exist in design/gdd/ besides game.md and systems-index.md.
Read:
design/gdd/game.mddesign/gdd/systems-index.md- all existing
design/gdd/*.mdexceptgame.mdandsystems-index.md design/art/art-direction.md- all existing
design/art/*-art.md .claude/docs/templates/plan/milestone.mdproduction/milestone.mdif exists
Phase 2: Hand Off To The Planner
Spawn gat-planner agent with all read content plus:
- instruction to write or update
production/milestone.md - instruction to define milestone directories using pattern
production/milestone-01-name/ - planning focus from argument if provided
The planner should:
- choose a small set of meaningful milestones
- give each a clear goal and named system set
- define code focus and art focus per milestone
- include sequencing notes and milestone-level risks
- keep milestone names short and path-safe
Phase 3: Review
Summarize how many milestones were planned and which comes first.
Use AskUserQuestion:
Plan first milestone (Recommended)→ Run/gat-planStop here