#Extension model

A3S Office is modular without pretending that every editor has the same interaction model. Document and Markdown surfaces accept TipTap extensions; spreadsheet, presentation, and PDF currently expose typed host ports while their internal command contexts remain private.

#TipTap extensions

import { Extension } from '@tiptap/core';
import { useMemo } from 'react';
import { DocumentEditor } from '@a3s-lab/office/react';

const ReviewShortcut = Extension.create({
  name: 'hostReviewShortcut',
  addKeyboardShortcuts() {
    return {
      'Mod-Shift-r': () => {
        this.editor.commands.focus();
        return true;
      },
    };
  },
});

export function Editor(props) {
  const extensions = useMemo(() => [ReviewShortcut], []);
  return <DocumentEditor {...props} extensions={extensions} />;
}

Rules:

1. Every extension needs a unique name; collisions with built-in extensions fail explicitly.
2. Keep the extension array reference stable.
3. Custom Nodes and Marks need matching DOCX or Markdown round-trip semantics.
4. Do not import implementation modules from @a3s-lab/office/internal paths.

#Host extension ports

The library never infers host behavior from localized labels or keyword matching. Selection-menu callbacks receive typed context and safe commands; the host owns prompts, model calls, authorization, and persistence.