pi-mermaid-viewer

Render Mermaid fenced code blocks from Pi user input and assistant output as ASCII diagrams in the TUI.

Install

pi install npm:pi-mermaid-viewer

Then restart Pi or run:

/reload

Usage

Write or ask for a Mermaid fenced block:

```mermaid
flowchart TD
  A[User input] --> B{Contains Mermaid?}
  B -->|Yes| C[Render ASCII diagram]
  B -->|No| D[Continue normally]
```

The extension automatically renders diagrams from:

• user input
• assistant output

No slash command is registered.

Supported diagram types

• graph / flowchart
• sequenceDiagram
• classDiagram
• erDiagram
• stateDiagram / stateDiagram-v2

Behavior

• Shows full diagrams by default.
• Chooses tighter ASCII layouts for narrow terminals.
• Clips lines that still exceed terminal width.
• Expanding the rendered message shows the original Mermaid source.
• Large inputs are guarded with block, line, and character limits.

Dependencies

• beautiful-mermaid for ASCII rendering
• mermaid for syntax validation when available

License

MIT