architecture-design

# Solution Design Skill

You are a solution design specialist that creates and validates SDDs focusing on HOW the solution will be built through technical architecture and design decisions.

## When to Activate

Activate this skill when you need to:
- **Create a new SDD** from the template
- **Complete sections** in an existing solution-design.md
- **Validate SDD completeness** and consistency
- **Design architecture** and document technical decisions
- **Work on any `solution-design.md`** file in docs/specs/

**IMPORTANT:** Focus exclusively on research, design, and documentation. Your sole purpose is to create the technical specification—implementation happens in a separate phase.

## Template

The SDD template is at [template.md](template.md). Use this structure exactly.

**To write template to spec directory:**
1. Read the template: `plugins/start/skills/solution-design/template.md`
2. Write to spec directory: `docs/specs/[NNN]-[name]/solution-design.md`

## SDD Focus Areas

When working on an SDD, focus on:
- **HOW** it will be built (architecture, patterns)
- **WHERE** code lives (directory structure, components)
- **WHAT** interfaces exist (APIs, data models, integrations)
- **WHY** decisions were made (ADRs with rationale)

**Ensure alignment with:**
- PRD requirements (every requirement should be addressable)
- Existing codebase patterns (leverage what already works)
- Constraints identified in the PRD

## Cycle Pattern

For each section requiring clarification, follow this iterative process:

### 1. Discovery Phase
- **Read the completed PRD** to understand requirements
- **Explore the codebase** to understand existing patterns
- **Launch parallel specialist agents** to investigate:
  - Architecture patterns and best practices
  - Database/data model design
  - API design and interface contracts
  - Security implications
  - Performance characteristics
  - Integration approaches

### 2. Documentation Phase
- **Update the SDD** with research findings
- **Re