Creating Diagrams with an Excalidraw Agent Skill and Excalidraw MCP

This article discusses how to create and maintain architecture diagrams using an Excalidraw agent skill and the Excalidraw MCP (Model Context Protocol) server integrated with GitHub Copilot in VS Code. It highlights the problem of traditional diagramming tools that live outside the engineering workflow, leading to outdated or unused diagrams. The approach allows engineers to describe systems in natural language within the editor, and GitHub Copilot generates live diagrams on an Excalidraw canvas, making diagrams part of the design loop rather than a separate task. The article covers setup, opinionated rules for drawing, and example diagrams for Azure architecture, GitHub Actions, and OAuth flows. It emphasizes keeping diagrams relevant by embedding them in the prompt-review-change cycle.