pdf-server: CommandQueue, Vercel deployment, improved tool description

examples/pdf-server/.gitignore

@@ -1,2 +1,4 @@
 dist/
 *.jsonl
+.vercel
+.env*.local

examples/pdf-server/.vercelignore

@@ -0,0 +1,5 @@
+node_modules
+src
+*.jsonl
+*.test.ts
+.vercel

examples/pdf-server/api/mcp.mjs

@@ -0,0 +1,70 @@
+// Polyfill DOMMatrix/ImageData/Path2D before pdfjs-dist loads.
+// Uses dynamic import() so polyfills execute before pdfjs-dist initializes.
+if (typeof globalThis.DOMMatrix === "undefined") {
+  globalThis.DOMMatrix = class DOMMatrix {
+    constructor(init) {
+      this.a = 1;
+      this.b = 0;
+      this.c = 0;
+      this.d = 1;
+      this.e = 0;
+      this.f = 0;
+      if (Array.isArray(init))
+        [this.a, this.b, this.c, this.d, this.e, this.f] = init;
+    }
+    get isIdentity() {
+      return (
+        this.a === 1 &&
+        this.b === 0 &&
+        this.c === 0 &&
+        this.d === 1 &&
+        this.e === 0 &&
+        this.f === 0
+      );
+    }
+    translate() {
+      return new DOMMatrix();
+    }
+    scale() {
+      return new DOMMatrix();
+    }
+    inverse() {
+      return new DOMMatrix();
+    }
+    multiply() {
+      return new DOMMatrix();
+    }
+    transformPoint(p) {
+      return p ?? { x: 0, y: 0 };
+    }
+    static fromMatrix() {
+      return new DOMMatrix();
+    }
+  };
+}
+if (typeof globalThis.ImageData === "undefined") {
+  globalThis.ImageData = class ImageData {
+    constructor(w, h) {
+      this.width = w;
+      this.height = h;
+      this.data = new Uint8ClampedArray(w * h * 4);
+    }
+  };
+}
+if (typeof globalThis.Path2D === "undefined") {
+  globalThis.Path2D = class Path2D {
+    moveTo() {}
+    lineTo() {}
+    bezierCurveTo() {}
+    quadraticCurveTo() {}
+    arc() {}
+    arcTo() {}
+    ellipse() {}
+    rect() {}
+    closePath() {}
+  };
+}
+
+// Dynamic import so polyfills above execute first.
+const { default: handler } = await import("../dist/http.js");
+export default handler;

examples/pdf-server/http.ts

@@ -0,0 +1,94 @@
+/**
+ * Vercel serverless handler for the PDF MCP server.
+ *
+ * Stateless: each request creates a fresh MCP server instance.
+ * The CommandQueue persists state across requests via Redis (Upstash).
+ *
+ * Deploy: vercel deploy --prod
+ * Env vars: UPSTASH_REDIS_REST_URL + TOKEN, or KV_REST_API_URL + TOKEN
+ */
+
+// Must be first import — pdfjs-dist checks for DOMMatrix at module init.
+import "./serverless-polyfills.js";
+
+import { StreamableHTTPServerTransport } from "@modelcontextprotocol/sdk/server/streamableHttp.js";
+import type { IncomingMessage, ServerResponse } from "node:http";
+import { createServer } from "./server.js";
+
+type Req = IncomingMessage & { body?: unknown };
+type Res = ServerResponse;
+
+function setCors(res: Res): void {
+  res.setHeader("Access-Control-Allow-Origin", "*");
+  res.setHeader("Access-Control-Allow-Methods", "GET, POST, DELETE, OPTIONS");
+  res.setHeader(
+    "Access-Control-Allow-Headers",
+    "Content-Type, Accept, Mcp-Session-Id",
+  );
+  res.setHeader("Access-Control-Expose-Headers", "Mcp-Session-Id");
+}
+
+export default async function handler(req: Req, res: Res): Promise<void> {
+  setCors(res);
+
+  if (req.method === "OPTIONS") {
+    res.writeHead(204);
+    res.end();
+    return;
+  }
+
+  if (req.method === "DELETE") {
+    res.writeHead(200);
+    res.end();
+    return;
+  }
+
+  const url = new URL(
+    req.url ?? "/",
+    `http://${req.headers.host ?? "localhost"}`,
+  );
+
+  if (url.pathname !== "/mcp" && url.pathname !== "/api/mcp") {
+    const redisUrl =
+      process.env.UPSTASH_REDIS_REST_URL ?? process.env.KV_REST_API_URL;
+    res.writeHead(200, { "Content-Type": "text/plain" });
+    res.end(
+      `PDF MCP Server\n\nMCP endpoint: ${url.origin}/mcp\n` +
+        `Redis: ${redisUrl ? "configured" : "not configured (in-memory)"}`,
+    );
+    return;
+  }
+
+  // Stateless: fresh server + transport per request.
+  // The interact tool + command queue require Redis for cross-request state.
+  // Without Redis, only read-only tools (list_pdfs, display_pdf) are exposed.
+  const hasRedis = !!(
+    process.env.UPSTASH_REDIS_REST_URL ?? process.env.KV_REST_API_URL
+  );
+  const server = createServer({ enableInteract: hasRedis });
+  const transport = new StreamableHTTPServerTransport({
+    sessionIdGenerator: undefined, // stateless — no sessions needed
+  });
+
+  res.on("close", () => {
+    transport.close().catch(() => {});
+    server.close().catch(() => {});
+  });
+
+  try {
+    await server.connect(transport);
+    await transport.handleRequest(req, res, req.body);
+  } catch (error) {
+    console.error("MCP error:", error);
+    if (!res.headersSent) {
+      res.writeHead(500, { "Content-Type": "application/json" });
+      res.end(
+        JSON.stringify({
+          jsonrpc: "2.0",
+          error: { code: -32603, message: "Internal server error" },
+          id: null,
+        }),
+      );
+    }
+  }
+}

examples/pdf-server/package.json

@@ -14,7 +14,7 @@
     "dist"
   ],
   "scripts": {
-    "build": "tsc --noEmit && cross-env INPUT=mcp-app.html vite build && tsc -p tsconfig.server.json && bun build server.ts --outdir dist --target node --external pdfjs-dist && bun build main.ts --outfile dist/index.js --target node --external \"./server.js\" --external pdfjs-dist --banner \"#!/usr/bin/env node\"",
+    "build": "tsc --noEmit && cross-env INPUT=mcp-app.html vite build && tsc -p tsconfig.server.json && bun build server.ts --outdir dist --target node --external pdfjs-dist && bun build main.ts --outfile dist/index.js --target node --external \"./server.js\" --external pdfjs-dist --banner \"#!/usr/bin/env node\" && bun build http.ts --outfile dist/http.js --target node --external pdfjs-dist",
     "watch": "cross-env INPUT=mcp-app.html vite build --watch",
     "serve": "bun --watch main.ts --enable-interact",
     "serve:stdio": "bun main.ts --stdio",