pi-rich-renderer

Local Pi extension that renders LaTeX formulas in assistant replies as tight terminal images.

It does not send rendered images to the model. Assistant context is restored to the original Markdown before the next LLM call.

Requirements

• Pi coding agent
• A TeX installation with latex and dvipng

On macOS with MacTeX these are usually available at /Library/TeX/texbin.

Install

From npm:

pi install npm:pi-rich-renderer

For local development, add the extension path to ~/.pi/agent/settings.json:

{
  "extensions": ["~/.pi/agent/extensions/pi-rich-renderer/index.ts"]
}

Then run /reload in Pi.

Configuration

Configure in ~/.pi/agent/settings.json or project-local .pi/settings.json:

{
  "richRenderer": {
    "imageScale": 0.5,
    "cacheTtlMs": 604800000
  }
}

• imageScale: terminal display scale for rendered formula images. Default 0.5.
• cacheTtlMs: delete cached PNGs older than this many milliseconds on extension load. Default 604800000 (7 days). Set 0 to disable cleanup.

Project .pi/settings.json overrides global settings.

Cache

Rendered PNGs are cached in:

~/.pi/cache/rich-renderer/

Cache keys are SHA-256 hashes of formula content, foreground color, and DPI.

Notes

• Code blocks are not rendered as images; Pi's native Markdown code rendering is preserved.
• Formulas inside fenced code blocks are ignored.
• The extension rewrites only the displayed assistant message; the next model context receives the original Markdown.