entity-model

Creates entity model documents with Mermaid.js ER diagrams and attribute tables defining entities, relationships, data types, and validation rules. Use when the user asks to "create an entity model", "design a data model", "draw an ERD", "define database schema", "model entities", or mentions entity-relationship diagram, ER diagram, database design, or data modeling. Also trigger whenever the task is to produce, write, or design an entity model or data model document (e.g. docs/entity_model.md) from a requirements catalog — including phrasings like "data model design", "the team needs an entity model before development", or a request to document entities with attributes, data types, precision, and validation or cross-attribute constraints.