@mdgate/visio

Convert Microsoft Visio drawings to Markdown in TypeScript.

@mdgate/visio reads .vsd, .vsdx, .vss, .vst, .vssx, and .vstx files directly in JavaScript and converts drawing text into GitHub-Flavored Markdown, without Python, native addons, WASM, or Visio.

Works in Node.js, Cloudflare Workers, Edge runtimes, and browsers.

npm install @mdgate/visio

import { toMarkdown } from '@mdgate/visio';

const markdown = await toMarkdown(bytes);

bytes is a Uint8Array, so the drawing can come from a file upload, object storage, an HTTP request, a browser file picker, or anywhere else your application gets bytes.

Why @mdgate/visio

Visio files hold process maps, network diagrams, and org charts. The useful content for an agent is usually the shape text, not a rendered image of the drawing.

@mdgate/visio is a Visio reader written for the same runtime as your application:

• Pure TypeScript
• Visio → Markdown locally
• No Python runtime
• No native addons
• No WASM runtime
• Zero third-party runtime dependencies
• Works with raw Uint8Array input
• Detects Visio packages and binary drawings from their contents, not only the filename

What it extracts

@mdgate/visio parses VSDX ZIP packages and binary VSD OLE files.

The converter extracts readable text from shapes and pages. It is not a visual renderer of the diagram.

The output is Markdown that can be searched, indexed, chunked, cached, or passed directly to an AI agent.

Node.js

import { readFile } from 'node:fs/promises';
import { toMarkdown } from '@mdgate/visio';

const bytes = new Uint8Array(await readFile('network.vsdx'));
const markdown = await toMarkdown(bytes);

console.log(markdown);

Browser

import { toMarkdown } from '@mdgate/visio';

const file = input.files![0];
const bytes = new Uint8Array(await file.arrayBuffer());

const markdown = await toMarkdown(bytes);

Cloudflare Workers and Edge runtimes

import { toMarkdown } from '@mdgate/visio';

export default {
  async fetch(request: Request) {
    const bytes = new Uint8Array(await request.arrayBuffer());
    const markdown = await toMarkdown(bytes);

    return new Response(markdown, {
      headers: {
        'content-type': 'text/markdown; charset=utf-8',
      },
    });
  },
};

Format detection

You do not need to trust the file extension.

@mdgate/visio recognizes Visio ZIP packages and OLE drawings from their contents.

const markdown = await toMarkdown(bytes);

A path can still be supplied as a format hint when @mdgate/visio is used through @mdgate/converters or a reader composed with @mdgate/core, but the path is never used to read a file from disk.

Compose it with other file readers

@mdgate/visio implements the converter interface from @mdgate/core.

import { create } from '@mdgate/core';
import { visio } from '@mdgate/visio';
import { pdf } from '@mdgate/pdf';

const read = create([
  visio(),
  pdf(),
]);

The application still uses one reading interface while each format remains independently installable.

Need more than Visio?

If your application needs to read many different file types, use the complete converter set:

npm install @mdgate/converters

import { toMarkdown } from '@mdgate/converters';

const markdown = await toMarkdown(bytes, {
  path: filename,
});

@mdgate/visio is one of the single-format packages in the open-source mdgate/converters project.

For AI agents, the same converter architecture can be used to extend read_file from text files to real-world document formats.

License

MIT