MCP File System

Implementation Reference

• src/index.ts:126-148 (registration)

  Full registration of the 'move_file' MCP tool, including schema definition and inline handler function.

  server.tool(
      "move_file",
      { source: z.string().describe("Source path"), destination: z.string().describe("Destination path") },
      async ({ source, destination }: { source: string, destination: string }) => {
          try {
              const validSource = validatePath(source);
              const validDest = validatePath(destination);
              
              // Check if destination exists
              try {
                  await fs.access(validDest);
                  throw new Error('Destination already exists');
              } catch (error: any) {
                  if (error.code !== 'ENOENT') throw error;
              }
  
              await fs.rename(validSource, validDest);
              return { content: [{ type: 'text', text: `Moved successfully: ${source} -> ${destination}` }] };
          } catch (error: any) {
              return { content: [{ type: 'text', text: `Error moving file/directory: ${error.message}` }] };
          }
      }
  );

• src/index.ts:129-147 (handler)

  Handler implementation for 'move_file' tool: validates paths using validatePath, ensures destination doesn't exist, performs fs.rename to move source to destination, and returns success/error text content.

  async ({ source, destination }: { source: string, destination: string }) => {
      try {
          const validSource = validatePath(source);
          const validDest = validatePath(destination);
          
          // Check if destination exists
          try {
              await fs.access(validDest);
              throw new Error('Destination already exists');
          } catch (error: any) {
              if (error.code !== 'ENOENT') throw error;
          }
  
          await fs.rename(validSource, validDest);
          return { content: [{ type: 'text', text: `Moved successfully: ${source} -> ${destination}` }] };
      } catch (error: any) {
          return { content: [{ type: 'text', text: `Error moving file/directory: ${error.message}` }] };
      }
  }

• src/index.ts:128-128 (schema)

  Zod input schema for 'move_file' tool defining 'source' and 'destination' as strings.

  { source: z.string().describe("Source path"), destination: z.string().describe("Destination path") },

• src/index.ts:14-20 (helper)

  Shared helper function validatePath used by move_file (and other tools) to ensure paths are within allowed directories before operations.

  function validatePath(filePath: string): string {
      const absolutePath = path.resolve(filePath);
      if (!allowedDirs.some(dir => absolutePath.startsWith(path.resolve(dir)))) {
          throw new Error(`Access denied: ${filePath} is not within allowed directories`);
      }
      return absolutePath;
  }