three-medium-extension

Contract-driven development is an approach to provider extension where you write Markdown contracts first, then YAML policy, and finally Python mechanism, ensuring strict separation of concerns and maintainability.

To extend a software provider, you follow the Three-Medium Architecture sequence: write Markdown contracts first, define YAML policy second, and implement Python mechanism third, strictly avoiding hardcoded policy in code.

Common anti-patterns to avoid during provider extension include hardcoding policy directly in Python mechanism code and skipping Markdown contract documentation, both of which compromise architectural separation and maintainability.

Yes, the Three-Medium Architecture requires Python for mechanism, YAML for policy, and Markdown for contracts to enforce a clear separation of concerns and maintainable provider extension development.

You need the Three-Medium Architecture when extending existing software providers with new capabilities, providing a structured development methodology that integrates features without compromising the provider's original architecture.