PDF-Tools MCP Server

Instructions

Implementation Reference

• index.ts:256-289 (handler)

  The handler logic for executing the 'generate_pdf_from_text' tool. It uses PDFKit to generate a PDF from text content, applies formatting options, validates and saves to the output path, and returns a success message.

  case "generate_pdf_from_text": {
    const { text_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 doc = new PDFDocument({
      margins: options.margins || { top: 50, left: 50, right: 50, bottom: 50 }
    });
    
    const stream = createWriteStream(outputPath);
    doc.pipe(stream);
    
    doc.font(options.font || 'Helvetica')
       .fontSize(options.fontSize || 12);
    
    doc.text(text_content);
    
    doc.end();
    
    return new Promise((resolve) => {
      stream.on('finish', () => {
        resolve({
          content: [
            {
              type: "text",
              text: `PDF successfully generated from text: ${outputPath}`
            }
          ]
        });
      });
    });
  }

• index.ts:95-134 (schema)

  The tool definition including name, description, and detailed inputSchema with properties, defaults, and required fields for the generate_pdf_from_text tool.

  {
    name: "generate_pdf_from_text",
    description: "Generate a PDF from plain text using PDFKit",
    inputSchema: {
      type: "object",
      properties: {
        text_content: {
          type: "string",
          description: "Text 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 formatting options",
          properties: {
            fontSize: { type: "number", default: 12 },
            font: { type: "string", default: "Helvetica" },
            margins: {
              type: "object",
              properties: {
                top: { type: "number", default: 50 },
                left: { type: "number", default: 50 },
                right: { type: "number", default: 50 },
                bottom: { type: "number", default: 50 }
              }
            }
          }
        }
      },
      required: ["text_content", "output_filename"]
    }
  },

• index.ts:175-177 (registration)

  Registration of the ListToolsRequestSchema handler, which returns the list of available tools including 'generate_pdf_from_text'.

  server.setRequestHandler(ListToolsRequestSchema, async () => {
    return { tools };
  });

• index.ts:30-41 (helper)

  Helper function used by the tool handler to validate that the output path is within allowed user directories for security.

  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;
  }