Open MCP Server

Implementation Reference

• src/tools/file-tools.ts:32-50 (handler)

  The execution handler for the 'read_file' MCP tool. Validates the file path existence, reads the file contents asynchronously using Node.js fs.promises.readFile, retrieves file statistics, and returns a structured response containing the text content and metadata including path, size, and encoding.

  async ({ path: filePath, encoding }) => {
    return wrapToolExecution(async () => {
      const validatedPath = await validatePathExists(filePath);
      const content = await fs.readFile(validatedPath, { encoding: encoding as FileEncoding });
      const stats = await fs.stat(validatedPath);
  
      return {
        content: [{ type: "text" as const, text: content }],
        metadata: {
          path: validatedPath,
          size: stats.size,
          encoding
        }
      };
    }, {
      errorCode: ERROR_CODES.FILE_OPERATION,
      context: "Failed to read file"
    });
  }

• src/tools/file-tools.ts:28-31 (schema)

  Zod input schema definition for the 'read_file' tool: 'path' is a required non-empty string, 'encoding' is an optional enum (utf8, utf-16le, latin1) defaulting to the configured default.

  {
    path: z.string().min(1, "Path is required"),
    encoding: z.enum(["utf8", "utf-16le", "latin1"]).optional().default(DEFAULTS.FILE_ENCODING)
  },

• src/tools/file-tools.ts:26-52 (registration)

  The registerReadFile function registers the 'read_file' tool on the MCP server instance using server.tool(), providing the name, Zod schema, and handler function.

  function registerReadFile(server: McpServer): void {
    server.tool("read_file",
      {
        path: z.string().min(1, "Path is required"),
        encoding: z.enum(["utf8", "utf-16le", "latin1"]).optional().default(DEFAULTS.FILE_ENCODING)
      },
      async ({ path: filePath, encoding }) => {
        return wrapToolExecution(async () => {
          const validatedPath = await validatePathExists(filePath);
          const content = await fs.readFile(validatedPath, { encoding: encoding as FileEncoding });
          const stats = await fs.stat(validatedPath);
  
          return {
            content: [{ type: "text" as const, text: content }],
            metadata: {
              path: validatedPath,
              size: stats.size,
              encoding
            }
          };
        }, {
          errorCode: ERROR_CODES.FILE_OPERATION,
          context: "Failed to read file"
        });
      }
    );
  }

• src/index.ts:65-65 (registration)

  Higher-level registration call to registerFileTools(server), which internally calls registerReadFile to add the 'read_file' tool among file-related tools.

  registerFileTools(server);