DiagramGPT — Eraser

How to generate a block diagram

Tips on making a Block Diagram

• Instead of writing a prompt from scratch, consider pasting excerpts from existing documents such as requirements docs, system documentation, or code.
• Working with an LLM to create a fleshed out diagram prompt can be effective. Describe the system or process that you’re trying to visualize and ask it to create a list of blocks, groupings, and their relationships.

1. Write a prompt describing how users interact with the system

A simple one-liner can work too but the best prompts are usually at least 3-4 sentences long. Applying the below framework generally yields good results:

• First, write out the structural components of the diagram. List out the blocks (components) as well as hierarchical groupings.
• Then, write out how those blocks should be connected. An easy way to do this is to write out the sequential flow of how data or a request travels through the system (e.g. User uploads file to web application).
• Include the visual requirements of a block diagram to the prompt: “Make a block diagram of components inside a PC. All nodes are rectangles. Create sensible groupings. The diagram title should include “block diagram.”

2. Make a diagram with the completed prompt

3. Edit the diagram with follow-up prompts (this step requires signing in to Eraser)

4. Manually adjust the layout using GUI controls (this step requires signing into Eraser)

Frequently asked questions

• Can I edit the generated block diagram?
  Yes. Click “Save and Edit Diagram” to open it in Eraser, where you can edit using diagram-as-code syntax or the visual GUI.

• What can I use as a prompt?
  Plain English, a nested list, or a code snippet. You can also paste excerpts from requirements docs, transcripts, or knowledge-base articles.

• Can I use this from an AI agent?
  Yes. Eraser runs an MCP server, so any MCP-compatible client – Claude, Cursor, or ChatGPT – can create and edit these diagrams directly.

• Who created this tool?
  The block diagram maker was created by the team at Eraser, leveraging frontier AI models. Eraser is an AI tool for technical design and documentation.

• Is it free?
  Generating a block diagram is free and requires no sign-up. Sign in to a free Eraser account to edit, save, and export your diagrams.

• Is there an API?
  Yes, you can read our API documentation. The API is only available to Starter, Business, and Enterprise Plan teams.

• Is there an MCP server?
  Yes. The Eraser MCP server lets an agent create, search, read, update and export diagrams from clients like Claude, Cursor, VS Code and ChatGPT. It is free to use, subject to the AI credit limits of your plan.

• Do you use my data to train AI models?
  No. Neither Eraser nor our model providers use your data to train AI models. Eraser may analyze usage to improve and enhance our AI features.

• How do I get started?
  Describe what you need in the prompt box above and generate. You can keep refining the result with follow-up prompts.

• What’s next for this tool?
  It only gets better from here. We’re working to improve accuracy and layout customization. If there’s something you’d like to see, drop us a note at hello@eraser.io.

• How do I get in touch?
  We’d love to hear from you. Reach out at hello@eraser.io, on X (@eraserlabs), or join our Slack community.