pdf-toolkit-mcp

Instructions

Implementation Reference

• src/tools/manipulate.ts:461-565 (handler)

  The tool `pdf_embed_qr_code` is defined and implemented in `src/tools/manipulate.ts`. It registers the tool with the MCP server, defines its input schema using `zod`, and handles the logic for generating a barcode (using `bwip-js`) and embedding it into a specified page of a PDF using `pdf-lib`.

  // ── pdf_embed_qr_code ───────────────────────────────────────────────
  server.registerTool(
    "pdf_embed_qr_code",
    {
      description:
        "Embed a QR code or barcode into a specific page of a PDF at given coordinates. Supports qrcode, code128, datamatrix, ean13, pdf417, and azteccode.",
      inputSchema: z
        .object({
          filePath: z
            .string()
            .max(4096)
            .describe("Absolute path to the source PDF file"),
          content: z
            .string()
            .min(1)
            .max(4096)
            .describe("Data to encode in the QR code or barcode"),
          outputPath: z
            .string()
            .max(4096)
            .describe("Absolute path for the output PDF"),
          page: z
            .number()
            .int()
            .min(1)
            .describe("Target page number (1-indexed)"),
          x: z
            .number()
            .describe("X position in points from the left edge"),
          y: z
            .number()
            .describe("Y position in points from the bottom edge"),
          size: z
            .number()
            .min(10)
            .max(1000)
            .optional()
            .describe("Size of the QR code/barcode in points. Defaults to 100."),
          type: z
            .enum(["qrcode", "code128", "datamatrix", "ean13", "pdf417", "azteccode"])
            .optional()
            .describe("Barcode type. Defaults to qrcode."),
        })
        .strict(),
      annotations: {
        readOnlyHint: false,
        destructiveHint: false,
        idempotentHint: true,
        openWorldHint: false,
      },
    },
    async ({ filePath, content, outputPath, page, x, y, size, type }) => {
      try {
        const resolvedPath = await validatePdfPath(filePath);
        await validateFileSize(resolvedPath);
        const resolvedOutput = await validateOutputPath(outputPath, filePath);
  
        const barcodeType = type ?? "qrcode";
        const barcodeSize = size ?? 100;
  
        // Generate barcode as PNG buffer
        const pngBuffer = await bwipToBuffer({
          bcid: barcodeType,
          text: content,
          scale: 3,
          includetext: false,
        });
  
        const pdfDoc = await loadExistingPdf(resolvedPath);
        const totalPages = pdfDoc.getPageCount();
  
        if (page > totalPages) {
          return toolError(
            `Page ${page} exceeds document length (${totalPages} pages).`
          );
        }
  
        const image = await pdfDoc.embedPng(pngBuffer);
        const targetPage = pdfDoc.getPage(page - 1);
  
        targetPage.drawImage(image, {
          x,
          y,
          width: barcodeSize,
          height: barcodeSize,
        });
  
        await savePdf(pdfDoc, resolvedOutput);
        const fileSize = await getFileSize(resolvedOutput);
  
        return toolSuccess({
          outputPath: resolvedOutput,
          page,
          type: barcodeType,
          position: { x, y },
          size: barcodeSize,
          fileSize,
        });
      } catch (error) {
        return toolError(
          error instanceof Error ? error.message : String(error)
        );
      }
    }
  );