Simple Document Processing MCP Server

Instructions

Implementation Reference

• src/tools/documentReader.ts:83-118 (handler)

  Core handler function that executes the document reading logic by determining file type and calling appropriate reader, returning success/data or error.

  export async function readFile(filePath: string) {
    try {
      const ext = path.extname(filePath).toLowerCase();
      let content: string;
  
      switch (ext) {
        case ".pdf":
          content = await readPDFFile(filePath);
          break;
        case ".docx":
          content = await readDocxFile(filePath);
          break;
        case ".txt":
          content = await readTextFile(filePath);
          break;
        case ".html":
          content = await readHTMLFile(filePath);
          break;
        case ".csv":
          content = await readCSVFile(filePath);
          break;
        default:
          throw new Error(`Unsupported file format: ${ext}`);
      }
  
      return {
        success: true,
        data: content,
      };
    } catch (error) {
      return {
        success: false,
        error: error instanceof Error ? error.message : "Unknown error",
      };
    }
  } 

• src/index.ts:59-75 (handler)

  MCP server request handler dispatch for 'document_reader' tool: validates input, calls readFile, formats response.

  if (name === "document_reader") {
    if (!isFileReaderArgs(args)) {
      throw new Error("Invalid arguments for document_reader");
    }
  
    const result = await readFile(args.filePath);
    if (!result.success) {
      return {
        content: [{ type: "text", text: `Error: ${result.error}` }],
        isError: true,
      };
    }
    return {
      content: [{ type: "text", text: result.data }],
      isError: false,
    };
  }

• src/tools/documentReader.ts:9-23 (schema)

  Tool definition with name, description, and input schema requiring 'filePath'.

  export const DOCUMENT_READER_TOOL: Tool = {
    name: "document_reader",
    description:
      "Read content from non-image document-files at specified paths, supporting various file formats: .pdf, .docx, .txt, .html, .csv",
    inputSchema: {
      type: "object",
      properties: {
        filePath: {
          type: "string",
          description: "Path to the file to be read",
        },
      },
      required: ["filePath"],
    },
  };

• src/tools/_index.ts:9-9 (registration)

  Exports array of all tools including DOCUMENT_READER_TOOL for server registration.

  export const tools = [DOCUMENT_READER_TOOL, PDF_MERGE_TOOL, PDF_SPLIT_TOOL, DOCX_TO_PDF_TOOL, DOCX_TO_HTML_TOOL, HTML_CLEAN_TOOL, HTML_TO_TEXT_TOOL, HTML_TO_MARKDOWN_TOOL, HTML_EXTRACT_RESOURCES_TOOL, HTML_FORMAT_TOOL, TEXT_DIFF_TOOL, TEXT_SPLIT_TOOL, TEXT_FORMAT_TOOL, TEXT_ENCODING_CONVERT_TOOL, EXCEL_READ_TOOL, FORMAT_CONVERTER_TOOL];

• src/tools/documentReader.ts:29-36 (helper)

  Type guard/validator for document_reader input arguments.

  export function isFileReaderArgs(args: unknown): args is FileReaderArgs {
    return (
      typeof args === "object" &&
      args !== null &&
      "filePath" in args &&
      typeof (args as FileReaderArgs).filePath === "string"
    );
  }