functional-design

To convert a PRD into a functional design document, you apply template-driven translation to generate system architecture, data models, and component specifications. This creates an engineering-ready design that aligns cross-functional teams.

A functional design document for system architecture includes component specifications, data model definitions, and Mermaid diagrams. It translates PRD content into visual models and structured templates to communicate design decisions clearly across teams.

You generate Mermaid diagrams for data models by running the PRD-to-FDD translation process. The skill applies visualization and modeling techniques to convert product requirements into clear Mermaid diagrams and structured data model definitions.

You need a prepared PRD to start drafting functional design templates. The skill requires product requirements as input to accurately generate system architecture diagrams, data models, and end-to-end component specifications for implementation.

The best way to structure component specifications is using template-driven design documents. By translating PRDs into standardized formats with data models and Mermaid diagrams, you ensure consistent handoffs and alignment between product, design, and engineering teams.

You should avoid template-driven functional design documents for projects lacking a defined PRD or those not requiring system architecture and data models. Without clear product requirements, the template cannot generate accurate component specifications or Mermaid diagrams.