contract-first-design

# Contract-First Design Skill

## When to Use This Skill

Use this skill when:

- **Contract First Design tasks** - Working on design and manage api contracts before implementation using openapi and asyncapi specifications for contract-first development
- **Planning or design** - Need guidance on Contract First Design approaches
- **Best practices** - Want to follow established patterns and standards

## Overview

Apply contract-first development methodology for APIs, ensuring specifications drive implementation.

## Contract-First Methodology

### Core Principles

```yaml
contract_first_principles:
  design_before_code:
    description: "API specification comes before implementation"
    benefits:
      - "Early feedback from consumers"
      - "Parallel development enabled"
      - "Clear contract for testing"
      - "Documentation from day one"

  specification_as_source_of_truth:
    description: "Spec is authoritative, code conforms to it"
    enforcement:
      - "Generate code from spec"
      - "Validate implementation against spec"
      - "CI/CD gates on spec compliance"

  consumer_centric:
    description: "Design for consumer needs, not provider convenience"
    practices:
      - "Involve consumers in design reviews"
      - "Consumer-driven contract testing"
      - "Gather real-world usage patterns"

  evolution_over_revolution:
    description: "Evolve contracts without breaking consumers"
    practices:
      - "Semantic versioning"
      - "Backward compatibility by default"
      - "Deprecation before removal"
```

### Development Workflow

```yaml
contract_first_workflow:
  phases:
    1_design:
      activities:
        - "Identify API consumers and use cases"
        - "Define resources and operations"
        - "Draft specification (OpenAPI/AsyncAPI)"
        - "Review with stakeholders"
      artifacts:
        - "Draft API specification"
        - "Use case documentation"
      gate: "Specification approved by consumers"

    2_validate: