Diagrams GitHub Repositories (2026) · Open Source Tools

Turn any idea, plan, or codebase into a beautiful interactive diagram. An agent skill for Claude Code, Codex, and more.

Virtual whiteboard for sketching hand-drawn like diagrams

AI-native knowledge base & Evernote/Obsidian alternative. Instant all-platform sync, rich notes (tables, mind maps, diagrams, posters), web clipper & MCP. 100% free on Cloudflare or Docker.

Generation of diagrams like flowcharts or sequence diagrams from text in a similar manner as markdown

Creates diagrams from textual descriptions!

Draw and edit draw.io diagrams by chatting with an AI. Web app, desktop app, and an MCP server for Claude Code, Cursor, Codex and VS Code.

Generate diagrams from textual description

An open-source service that generates image URLs for diagrams based on the provided Mermaid code.

The missing pieces for Unreal's PCG. Graph theory, advanced pathfinding, spatial ops, filtering, asset management, and more.

Your diagrams, as requested. A clean-room, headless Rust core for Visio's .vsdx files and ShapeSheet, with a CLI and an MCP server.

HedgeDoc - Ideas grow better together

Visualize, collaborate, and evolve the software architecture with always actual and live diagrams from your code

Command line tool for the Mermaid library

A Unicode canvas for humans and AI. Draw diagrams, interfaces, and slides as editable text.

Animated, explorable diagrams for Claude and other coding agents, from a short JSON spec.

Arkdraw is an open-source diagramming app for creating flowcharts, UML, ER diagrams, network maps, wireframes, and mind maps with a built-in AI assistant that generates and edits diagrams from natural-language prompts.

Generate Kubernetes architecture diagrams from Kubernetes manifest files, kustomization files, Helm charts, helmfiles, and actual cluster state