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Deploy with Deno or Bun

Deno and Bun both serve web-standard handlers natively, so the MCP handler plugs straight into their built-in servers. Each example below serves the static site and /mcp from one process.

Deno​

main.js
import { serveDir } from 'jsr:@std/http/file-server';
import { createWebRequestHandler } from 'docusaurus-plugin-mcp-server/adapters';
import bundle from './build/mcp/bundle.json' with { type: 'json' };

const mcp = createWebRequestHandler({ artifacts: bundle });

Deno.serve(async (request) => {
  const url = new URL(request.url);
  if (url.pathname === '/mcp') {
    return mcp(request);
  }
  const response = await serveDir(request, { fsRoot: 'build', quiet: true });
  if (response.status !== 404 || url.pathname.endsWith('/')) {
    return response;
  }
  // With trailingSlash: false, Docusaurus writes /docs/intro as docs/intro.html.
  url.pathname += '.html';
  return serveDir(new Request(url, request), { fsRoot: 'build', quiet: true });
});

Deno resolves docusaurus-plugin-mcp-server from your package.json and node_modules. Run it locally:

npm run build
deno run --allow-net --allow-read --allow-env --allow-sys main.js

The server listens on http://localhost:8000, with the endpoint at http://localhost:8000/mcp.

On Deno Deploy, create an app from your repository with:

  • Install command: npm ci
  • Build command: npm run build
  • Entrypoint: main.js

The build has to run before the entrypoint is loaded, because main.js imports build/mcp/bundle.json.

Bun​

server.js
import { createWebRequestHandler } from 'docusaurus-plugin-mcp-server/adapters';
import bundle from './build/mcp/bundle.json' with { type: 'json' };

const mcp = createWebRequestHandler({ artifacts: bundle });

// Serve build/ for every other path: /docs/intro → build/docs/intro.html or build/docs/intro/index.html
async function serveStatic(request) {
  const { pathname } = new URL(request.url);
  for (const candidate of [pathname, `${pathname}.html`, `${pathname}/index.html`]) {
    const file = Bun.file(`./build${candidate}`);
    if (await file.exists()) {
      return new Response(file);
    }
  }
  return new Response(Bun.file('./build/404.html'), { status: 404 });
}

Bun.serve({
  port: Number(process.env.PORT ?? 3000),
  routes: { '/mcp': mcp },
  fetch: serveStatic,
});
npm run build
bun server.js

The endpoint is at http://localhost:3000/mcp. To run it in production, start bun server.js on any host that runs a long-lived process (a VM, a container, Fly.io, Railway, Render). Run npm run build in the image build so build/ ships with it.

Check it​

Use your server's public URL:

curl https://docs.example.com/mcp

You should get the status JSON.

Notes​

  • One import form for both. with { type: 'json' } is required by Deno and accepted by Bun.
  • Only MCP? If something else serves the static site, drop the static handling and serve mcp alone: Deno.serve(mcp) or Bun.serve({ fetch: mcp }). Then set server.url to wherever the endpoint ends up.

Something not working? See Troubleshooting.