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Claude Code Mermaid
A Claude Code plugin that renders Mermaid diagrams as Unicode art directly in the terminal while replies stream, fully offline.
Technologies
JavaScriptNode.jsWebAssemblyMermaidClaude Code
Live terminal diagrams: A MessageDisplay hook replaces Mermaid blocks in Claude’s visible replies with Unicode drawings once each closing fence arrives. The original transcript stays intact.
Diagram coverage: Supports flowcharts, sequence diagrams, state diagrams, class diagrams, and entity relationship diagrams. If rendering fails or exceeds terminal width, the source remains visible with a reason.
Offline tooling: Bundles a WebAssembly renderer, a skill for creating and checking diagrams, and a CLI for rendering Mermaid files or Markdown documents.