entity-relationship-diagram
Turn a data model into an entity-relationship (ER) diagram. Use when asked to design a schema, model data, show how tables/entities relate, or diagram a database. Produces a ready-to-render Mermaid ER diagram (renders live, exportable as PNG/SVG) plus key attributes, cardinality, and design notes.
npx skills add mohitagw15856/pm-claude-skills --skill entity-relationship-diagram --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Entity-Relationship Diagram Skill Before you write a migration, it pays to see the data model: the entities, their key fields, and how they relate (one-to-many, many-to-many). This skill turns a described domain into a clean **Mermaid ER diagram** with proper cardinality notation and the attributes that matter. ## Required Inputs Ask for these only if they aren't already provided: - **The entities** — the core objects/tables (User, Order, Product…). - **Relationships** — how they relate, and the cardinality (a user *has many* orders, an order *has many* line items). - **Key attributes** — the important fields per entity (especially keys); full column lists aren't required. - **The domain** — what the system does, so the model is realistic. ## Output Format ### [Domain] — data model One line on the scope of the model. ```mermaid erDiagram USER ||--o{ ORDER : places ORDER ||--|{ LINE_ITEM : contains PRODUCT ||--o{ LINE_ITEM : "appears in" USER { uuid id PK string email string name } ORDER { uuid id PK uuid user_id FK datetime created_at string status } LINE_ITEM { uuid id PK uuid order_id FK uuid product_id FK int qty } PRODUCT { uuid id PK string name decimal price } ``` **Cardina
- Required Inputs
- Output Format
- [Domain] — data model
- Mermaid Rules (so it renders)
- Quality Checks
- Anti-Patterns
- Based On
What does the entity-relationship-diagram skill do?
Turn a data model into an entity-relationship (ER) diagram. Use when asked to design a schema, model data, show how tables/entities relate, or diagram a database. Produces a ready-to-render Mermaid ER diagram (renders live, exportable as PNG/SVG) plus key attributes, cardinality, and design notes.
How do I install it?
Run `npx skills add mohitagw15856/pm-claude-skills --skill entity-relationship-diagram --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From mohitagw15856/pm-claude-skills, a repository with 1,255 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.