---
title: ToolRouter — Agent Use Case Guide
description: Step-by-step guide for completing a task with a specific AI agent using ToolRouter.
url: https://toolrouter.com/tools/diagram-generator/use-cases/create-entity-relationship-diagrams/chatgpt
---
# How to Create ER Diagrams with ChatGPT

ChatGPT creates ER diagrams while offering data modeling advice. It can suggest normalization improvements, flag potential issues with your relationship design, and generate both simplified overview diagrams and detailed versions with all columns and types. The diagramming process doubles as a design review.

## Setup

{"mcpServers":{"toolrouter":{"command":"npx","args":["-y","toolrouter-mcp"]}}}

## Steps

1. Configure ToolRouter in ChatGPT
2. Ask: "Generate an ER diagram for this database schema" and describe the entities
3. ChatGPT creates the diagram with proper cardinality notation
4. Request: "Add indexes and constraints to the diagram"

## Example Prompt

```
Create an ER diagram for a blog platform: Users write Posts, Posts have many Comments, Posts have many Tags through a PostTags join table. Show all columns with types.
```

## Tips

- ChatGPT can suggest normalization improvements while creating the diagram
- Ask for both a simplified overview diagram and a detailed one with all columns
