entity-modelling

Classify concepts as entities or enumerations and define inheritance relationships.

1|Updated Feb 7, 2026
One-click install
npx skills add https://github.com/Semprini/md-ddl --skill entity-modelling
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: entity-modelling
Source: https://github.com/Semprini/md-ddl/tree/main/agents/agent-ontology/skills/entity-modelling
Command: npx skills add https://github.com/Semprini/md-ddl --skill entity-modelling

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This Skill helps you accurately classify concepts as entities or enumerations, define their relationships, and decide on inheritance patterns, preventing common modeling errors.

Core Features & Use Cases

  • Concept Classification: Distinguishes between first-class entities, enums, attributes, and relationship attributes.
  • Inheritance Design: Guides the creation of logical subtype hierarchies.
  • Attribute Definition: Ensures correct definition of entity attributes, constraints, and enumerations.
  • Use Case: When unsure whether "Customer" should be a standalone entity or just a type of "Party," this skill provides the framework to make the correct decision based on business ownership and attributes.

Quick Start

Use the entity-modelling skill to help classify the concept of 'Product' as either an entity or an enum.

Frequently Asked Questions about entity-modelling

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I decide if a concept should be modeled as an entity or an enumeration?

Concept classification distinguishes first-class entities from enums by evaluating business ownership and attributes. If a concept requires independent existence and multiple attributes, it is an entity; if it represents a fixed set of values, it is an enumeration.

What is the best way to structure entity inheritance hierarchies in data modeling?

Inheritance design in data modeling involves creating logical subtype hierarchies based on shared attributes and business rules. This skill guides decisions on whether a concept like 'Customer' should be a standalone entity or a subtype of 'Party' to prevent hierarchy errors.

How do you define attributes and constraints for an entity YAML structure?

Entity YAML structure requires defining attributes and constraints precisely to avoid ambiguity in concept realization. This process ensures correct definition of entity attributes, constraints, and enumeration values based on user stories and industry standards.

When should I track existence, mutability, and temporal states in entity design?

Entity design tracks existence, mutability, and temporal states based on specific user stories and industry standards. This skill guides these decisions to ensure your data model accurately reflects business requirements and lifecycle changes.

Can I use this skill to resolve ambiguity in conceptual data modeling?

Yes, conceptual data modeling resolves ambiguity by classifying concepts precisely, defining attributes, and establishing inheritance relationships. This skill provides the framework to make correct decisions regarding first-class entities, enums, and relationship attributes.

How to classify 'Product' as either an entity or an enum?

To classify 'Product' as an entity or an enum, you evaluate its characteristics within your data modeling context. If 'Product' has independent attributes and business ownership, it is an entity; if it is a fixed list, it is an enum.