Implementation Planner

Transform a feature specification into actionable technical design and tasks.

Triggers

• "implement FEAT-XXX" (in plan mode or normal)
• "plan implementation for FEAT-XXX"
• "create implementation plan for FEAT-XXX"
• "generate tasks for FEAT-XXX"
• "create technical design for FEAT-XXX"

Prerequisites

• Feature folder must exist: docs/features/FEAT-XXX/
• spec.md must be completed (interview done)
• analysis.md should exist (think critically done)
• If spec incomplete: "Let's first interview about this feature"

Purpose

Create:

1. design.md - Technical architecture for the feature
2. tasks.md - Granular, actionable implementation tasks
3. Update status.md - Mark phase as "Plan complete"

Process

1. Read Context

# Read feature spec
cat docs/features/FEAT-XXX/spec.md

# Read analysis (from Think Critically phase)
cat docs/features/FEAT-XXX/analysis.md

# Read project architecture for consistency
cat docs/architecture/_index.md 2>/dev/null

# Read project context
cat docs/project.md 2>/dev/null

# Check current status
cat docs/features/FEAT-XXX/status.md

2. Generate design.md

Based on spec.md and analysis.md, create technical design covering:

Required sections:

• Overview (brief technical approach)
• Architecture (ASCII diagram + components table)
• Data Model (models, relationships)
• API Design (endpoints, request/response examples)
• Service Layer (services, business logic)
• Error Handling (error cases, responses)
• Security Considerations
• Performance Considerations
• Dependencies (external + internal)
• File Structure (new files + modified files)
• Implementation Order

3. Generate tasks.md

Break design into granular, actionable tasks:

Task rules:

• Each task = 15-60 minutes of work
• Each task = ONE commit
• Tasks ordered by dependency
• Each task starts with a verb (Create, Add, Implement, Update, Test)
• Each task has clear "done" criteria

4. Update status.md

CRITICAL: Always update status after generating plan

5. Update Global Status

CRITICAL: Update docs/features/_index.md

6. Completion Message

After generating plan:

Implementation plan created for FEAT-XXX

Generated:
- docs/features/FEAT-XXX/design.md (technical design)
- docs/features/FEAT-XXX/tasks.md (X tasks)

Updated:
- docs/features/FEAT-XXX/status.md (Phase: Plan complete)
- docs/features/_index.md (global status)

Next steps:
1. Create branch: git checkout -b feature/XXX-name
2. Start implementation: "Execute FEAT-XXX tasks"
   Or fork for parallel: /fork-feature FEAT-XXX full