Getting Started — Specification-Driven Development

This guide walks you through the core concepts of SDD and gets you productive in minutes.

What is SDD?

Specification-Driven Development (SDD) is a workflow where you define WHAT you want to build before writing any code. The specification becomes a contract between your idea and the implementation, enforced through automated quality gates.

Idea → Specification → Tasks → Implementation → Review → Cleanup → Done
       (brainstorm)  (spec-to-tasks)             (task-review)  (code-cleanup)

Why SDD?

• Eliminates ambiguity: Every feature is defined functionally before coding starts
• Traceability: Every line of code traces back to a requirement
• Quality gates: Automated review ensures nothing is missed
• Living docs: Specifications evolve alongside the codebase

Prerequisites

• Claude Code installed and configured
• Python 3.11+ (for hook scripts and Ralph Loop automation)
• developer-kit-core plugin installed (provides general-purpose agents)
• A git repository with at least one commit

Installation

# Install the plugin from marketplace
/plugin marketplace add giuseppe-trisciuoglio/developer-kit

# Or install from local directory
/plugin install /path/to/developer-kit/plugins/developer-kit-specs

Verify installation:

/help
# You should see /developer-kit-specs:specs.brainstorm, /developer-kit-specs:specs.spec-to-tasks, etc.

Your First Specification

Let's build a real feature: user authentication with JWT tokens for a Spring Boot application.

Step 1: Brainstorm the Idea

/developer-kit-specs:specs.brainstorm Add user authentication with JWT tokens for a Spring Boot REST API

Claude will guide you through a 9-phase process:

1. Context Discovery — Analyzes your project structure, existing code patterns, dependencies
2. Complexity Assessment — Checks if the idea should be split into multiple specifications
3. Idea Refinement — Asks up to 3 clarifying questions (e.g., "Should refresh tokens be supported?")
4. Functional Approach Exploration — Presents 2-3 approaches, focusing on WHAT not HOW
5. Contextual Codebase Exploration — Examines existing security config, user entities, etc.
6. Specification Presentation — Shows the functional specification section by section
7. Specification Generation — Creates the full spec document
8. Quality Review — Verifies completeness and consistency
9. Summary — Lists outputs and recommended next steps

Output files created:

docs/specs/001-user-auth/
├── 2026-04-10--user-auth.md        # Main functional specification
├── user-request.md                  # Your original request
├── brainstorming-notes.md           # Session context and decisions
└── decision-log.md                  # Decision audit trail

The specification is technology-agnostic. It describes behaviors, not implementation details.

Step 2: Convert to Tasks

/developer-kit-specs:specs.spec-to-tasks --lang=spring docs/specs/001-user-auth/

Claude analyzes your specification and generates executable tasks:

1. Reads the specification and extracts functional requirements
2. Explores your codebase to understand existing patterns (Spring Security, User entities, etc.)
3. Breaks requirements into tasks — atomic, testable units with clear acceptance criteria
4. Generates a traceability matrix mapping requirements to tasks

Output files created:

docs/specs/001-user-auth/
├── 2026-04-10--user-auth--tasks.md    # Task index
├── knowledge-graph.json                # Cached codebase analysis
├── traceability-matrix.md             # Requirements → Tasks mapping
└── tasks/
    ├── TASK-001.md    # Create User entity and repository
    ├── TASK-002.md    # Implement JWT token service
    ├── TASK-003.md    # Create authentication endpoints
    ├── TASK-004.md    # Add Spring Security configuration
    ├── TASK-005.md    # Write e2e tests for auth flow
    └── TASK-006.md    # Code cleanup and finalization

Each task file contains:

• Frontmatter: ID, title, status, dependencies, provides/expects contracts
• Description: What to implement
• Acceptance Criteria: Checkboxes for verification
• Definition of Done: Quality checklist

Step 3: Implement a Task

/developer-kit-specs:specs.task-implementation --lang=spring --task="docs/specs/001-user-auth/tasks/TASK-001.md"

Claude follows a structured 12-step process:

1. Validates prerequisites — Checks git state, task dependencies, contracts
2. Implements the code — Writes production code following your project conventions
3. Runs verification — Executes tests, validates acceptance criteria
4. Updates task status — Automatically marks in_progress → implemented

Hooks fire automatically:

• task-auto-status.py updates the task frontmatter based on checkbox changes
• task-kpi-analyzer.py calculates quality KPIs and saves them to TASK-001--kpi.json

Step 4: Review the Implementation

/developer-kit-specs:specs.task-review --lang=spring docs/specs/001-user-auth/tasks/TASK-001.md

The review validates 4 dimensions:

Output: TASK-001--review.md with pass/fail status and detailed findings.

Step 5: Clean Up and Complete

If the review passes:

/developer-kit-specs:specs-code-cleanup --lang=spring --task="docs/specs/001-user-auth/tasks/TASK-001.md"

This final step:

• Removes debug logs (System.out.println, temporary comments)
• Optimizes imports
• Runs language-specific formatters (./mvnw spotless:apply)
• Verifies tests still pass
• Marks the task as completed

Step 6: Sync Specification with Implementation

After implementing several tasks, sync the spec with reality:

/developer-kit-specs:specs.spec-sync-with-code docs/specs/001-user-auth/

This detects deviations (scope expansions, refinements, reductions) and updates the specification to match what was actually built.

What's Next?

• SDD Workflow — Complete workflow documentation with all phases
• Commands Reference — Detailed command documentation with examples
• Ralph Loop Guide — Automate task execution across multiple agents (manual and fully automated via agents_loop.py)
• TDD Workflow — Test-Driven Development integration
• KPI Evaluation — Understanding quality metrics and scoring

Quick Reference