PDF-Tools MCP Server

Instructions

Implementation Reference

• index.ts:184-219 (handler)

  The handler function for the 'generate_pdf_from_html' tool. It validates the output path, launches a headless Puppeteer browser, loads the HTML content into a page, generates the PDF with specified options, and returns a success message with the file path.

  case "generate_pdf_from_html": {
    const { html_content, output_filename, output_dir = DEFAULT_OUTPUT_DIR, options = {} } = args as any;
    
    const outputPath = validateOutputPath(path.join(output_dir, output_filename));
    
    await fs.mkdir(path.dirname(outputPath), { recursive: true });
    
    const browser = await puppeteer.launch({ headless: true });
    const page = await browser.newPage();
    
    await page.setContent(html_content, { waitUntil: 'networkidle0' });
    
    const pdfOptions = {
      path: outputPath,
      format: options.format || 'A4',
      margin: options.margin || {
        top: '1cm',
        right: '1cm', 
        bottom: '1cm',
        left: '1cm'
      },
      printBackground: true
    };
    
    await page.pdf(pdfOptions as any);
    await browser.close();
    
    return {
      content: [
        {
          type: "text",
          text: `PDF successfully generated from HTML: ${outputPath}`
        }
      ]
    };
  }

• index.ts:59-93 (schema)

  Input schema definition for the 'generate_pdf_from_html' tool, specifying parameters like html_content (required), output_filename (required), output_dir (optional), and options for PDF formatting.

  inputSchema: {
    type: "object",
    properties: {
      html_content: {
        type: "string",
        description: "HTML content to convert to PDF"
      },
      output_filename: {
        type: "string", 
        description: "Name of the output PDF file (without path)"
      },
      output_dir: {
        type: "string",
        description: "Output directory (optional, defaults to Downloads)",
        default: DEFAULT_OUTPUT_DIR
      },
      options: {
        type: "object",
        description: "PDF generation options",
        properties: {
          format: { type: "string", default: "A4" },
          margin: {
            type: "object",
            properties: {
              top: { type: "string", default: "1cm" },
              right: { type: "string", default: "1cm" }, 
              bottom: { type: "string", default: "1cm" },
              left: { type: "string", default: "1cm" }
            }
          }
        }
      }
    },
    required: ["html_content", "output_filename"]
  }

• index.ts:56-94 (registration)

  Tool registration in the tools array, including name, description, and input schema. This is returned by ListToolsRequestHandler.

  {
    name: "generate_pdf_from_html",
    description: "Generate a PDF from HTML content using Puppeteer",
    inputSchema: {
      type: "object",
      properties: {
        html_content: {
          type: "string",
          description: "HTML content to convert to PDF"
        },
        output_filename: {
          type: "string", 
          description: "Name of the output PDF file (without path)"
        },
        output_dir: {
          type: "string",
          description: "Output directory (optional, defaults to Downloads)",
          default: DEFAULT_OUTPUT_DIR
        },
        options: {
          type: "object",
          description: "PDF generation options",
          properties: {
            format: { type: "string", default: "A4" },
            margin: {
              type: "object",
              properties: {
                top: { type: "string", default: "1cm" },
                right: { type: "string", default: "1cm" }, 
                bottom: { type: "string", default: "1cm" },
                left: { type: "string", default: "1cm" }
              }
            }
          }
        }
      },
      required: ["html_content", "output_filename"]
    }
  },

• index.ts:30-41 (helper)

  Helper function to validate that the output path is within allowed user directories (Downloads, Documents, Desktop). Used in the handler.

  function validateOutputPath(outputPath: string): string {
    const resolvedPath = path.resolve(outputPath);
    const isAllowed = ALLOWED_DIRS.some(allowedDir => 
      resolvedPath.startsWith(path.resolve(allowedDir))
    );
    
    if (!isAllowed) {
      throw new Error(`Output path must be within allowed directories: ${ALLOWED_DIRS.join(", ")}`);
    }
    
    return resolvedPath;
  }