Oh-My-Mermaid: Claude Code Skill for Auto-Generating Architecture Diagrams

Oh-My-Mermaid is a Claude Code skill that automatically generates architecture diagrams and documentation from codebases. The tool uses Claude Code to analyze code, identify architectural patterns, and write Mermaid diagrams.

Key Details

The tool is installed globally via npm:

npm install -g oh-my-mermaid && omm setup

In Claude Code, you use the skill with:

/omm-scan (skill) → omm view

The developer emphasizes several design principles:

• Zero runtime dependencies (just YAML)
• Claude Code writes the diagrams while the CLI owns the files
• Plain text output (.mmd + markdown) that's fully git-diffable
• Recursive analysis where complex modules get nested diagrams

The project is free and open source under the MIT license. The GitHub repository is available at https://github.com/oh-my-mermaid/oh-my-mermaid.

A demo video and preview image are available through the Reddit post, and there's a live exploration link at https://ohmymermaid.com/share/8fca9ff0fef84a139ac2d3f9875db0d2.

This type of tool is useful for developers who need to quickly understand or document the architecture of existing codebases, particularly when onboarding to new projects or conducting code reviews.