image-reader MCP Server

Instructions

Implementation Reference

• src/index.ts:513-580 (handler)

  The execution logic for the scan_directory tool. It validates input, scans the directory (recursively if specified), filters for supported image formats, retrieves metadata for each image using getImageMetadata, and returns a text content block with a JSON summary of found images.

  case "scan_directory": {
    const { directory, recursive = false } = 
      request.params.arguments as { directory: string, recursive?: boolean };
    
    if (!directory) {
      throw new McpError(ErrorCode.InvalidParams, "Directory path is required");
    }
    
    if (!fs.existsSync(directory)) {
      throw new McpError(ErrorCode.InvalidRequest, `Directory not found: ${directory}`);
    }
    
    try {
      // Function to scan directory recursively
      async function scanDir(dir: string, results: ImageMetadata[] = []): Promise<ImageMetadata[]> {
        // Use fs instead of fsExtra for readdir
        const entries = await fs.promises.readdir(dir, { withFileTypes: true });
        
        for (const entry of entries) {
          const fullPath = path.join(dir, entry.name);
          
          if (entry.isDirectory() && recursive) {
            await scanDir(fullPath, results);
          } else if (entry.isFile()) {
            const ext = path.extname(entry.name).toLowerCase();
            if (SUPPORTED_FORMATS.includes(ext)) {
              try {
                const metadata = await getImageMetadata(fullPath);
                results.push(metadata);
              } catch (error) {
                console.error(`Error processing ${fullPath}:`, error);
              }
            }
          }
        }
        
        return results;
      }
      
      const images = await scanDir(directory);
      
      return {
        content: [
          {
            type: "text",
            text: `Found ${images.length} images in ${directory}${recursive ? ' (including subdirectories)' : ''}:\n\n` +
              JSON.stringify(images.map(img => ({
                filename: img.filename,
                path: img.path,
                format: img.format,
                dimensions: `${img.width}x${img.height}`,
                size: `${(img.size / 1024).toFixed(2)} KB`
              })), null, 2)
          }
        ]
      };
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: `Error scanning directory: ${error instanceof Error ? error.message : String(error)}`
          }
        ],
        isError: true
      };
    }
  }

• src/index.ts:309-326 (registration)

  Registration of the scan_directory tool in the ListToolsRequestSchema handler, including its name, description, and input schema.

  {
    name: "scan_directory",
    description: "Scan a directory for images and return metadata",
    inputSchema: {
      type: "object",
      properties: {
        directory: {
          type: "string",
          description: "Directory path to scan for images"
        },
        recursive: {
          type: "boolean",
          description: "Whether to scan subdirectories recursively"
        }
      },
      required: ["directory"]
    }
  }

• src/index.ts:312-324 (schema)

  Input schema definition for the scan_directory tool, specifying directory (required) and optional recursive flag.

  inputSchema: {
    type: "object",
    properties: {
      directory: {
        type: "string",
        description: "Directory path to scan for images"
      },
      recursive: {
        type: "boolean",
        description: "Whether to scan subdirectories recursively"
      }
    },
    required: ["directory"]