@herbertgao/pi-mermaid-open

HerbertGao-maintained fork of @tifan/pi-mermaid-open, distributed under MIT with the original attribution preserved.

Find Mermaid diagrams that Pi left unrendered and show one in a terminal image viewer.

How it works

Scans assistant messages in the current branch for ```mermaid and ```mmd fences.
Hides diagrams that Pi already rendered and labels skipped diagrams by reason.
Renders diagrams as 4x PNGs with @mermaid-js/mermaid-cli.
Uses a non-blocking Herdr overlay with Kitty graphics when available.
Uses Pi's image viewer in other TUI sessions.
Saves PNGs under <agent-dir>/artifacts/mermaid/ outside TUI mode.
In Herdr, use +/= and - to zoom, h/j/k/l or the arrow keys to pan, 0 to reset, and Enter or Escape to close.

pi install npm:@herbertgao/pi-mermaid-open

Bun is optional. The extension uses bunx -y @mermaid-js/mermaid-cli when Bun is available and falls back to npx -y @mermaid-js/mermaid-cli.
Herdr with Kitty graphics support is optional. In a compatible Herdr TUI session, /mermaid-open automatically links the bundled Herdr plugin, so you do not need to install it separately. Other TUI sessions use Pi's image viewer.
Network access on first use unless Mermaid CLI is already cached.
A Chromium browser available to Puppeteer. The extension skips Puppeteer's automatic browser download, so Puppeteer must find an existing cache or configured browser executable.

/mermaid-open: Pick a Mermaid diagram from recent assistant messages, render it, and open the PNG.