Generate Implementation Plan

Generate an implementation design document from a canonical specification.

Workflow

1. Load Specification

   • Read the specification file from provided path
   • If no path provided, search .specs/ for recent specifications
   • Parse requirements and acceptance criteria

2. Analyze Codebase

   • Explore existing codebase for:
     • Existing patterns and conventions
     • Related components and modules
     • Integration points
     • Technology stack

3. Generate Design

   • Create implementation approach
   • Identify components to create/modify
   • Define data models (if applicable)
   • Design API contracts (if applicable)
   • Document alternatives considered
   • Map design elements to requirements

4. Validate Coverage

   • Verify design addresses all requirements
   • Check alignment with codebase conventions
   • Identify risks and mitigation strategies

5. Save Design

   • Save to .specs/{feature-name}/design.md
   • Update specification with design reference
   • Report design summary

Arguments

• $ARGUMENTS - Path to specification file

Examples

# From specification file
/spec-driven-development:plan .specs/user-auth/spec.md

# Auto-detect recent specification
/spec-driven-development:plan

Design Document Structure

# Design: {Feature Name}

## Overview
[High-level implementation approach]

## Components

### {Component 1}
- **Responsibility:** [What it does]
- **Location:** [File path]
- **Interfaces:** [How it connects]

## Data Model
[Entity definitions if applicable]

## API Design
[Endpoint specifications if applicable]

## Alternatives Considered
[Other approaches and why rejected]

## Requirements Coverage
| Requirement | Covered By |
| --- | --- |
| FR-1 | Component A |
| FR-2 | Component B |

Related Commands

• /spec-driven-development:specify - Generate specification (Phase 1)
• /spec-driven-development:tasks - Generate task breakdown (Phase 3)
• /spec-driven-development:implement - Guide implementation (Phase 4)