Open Food Facts MCP Server

Instructions

Implementation Reference

• src/handlers.ts:7-32 (handler)

  Main handler function for the 'get_product' tool. Fetches product data from the client and returns formatted text response or not found message.

  async handleGetProduct(barcode: string) {
    const response = await this.client.getProduct(barcode);
    
    if (response.status === 0 || !response.product) {
      return {
        content: [
          {
            type: "text" as const,
            text: `Product not found for barcode: ${barcode}`,
          },
        ],
      };
    }
  
    const product = response.product;
    const formattedProduct = this.formatProduct(product);
  
    return {
      content: [
        {
          type: "text" as const,
          text: formattedProduct,
        },
      ],
    };
  }

• src/tools.ts:5-17 (schema)

  Input schema and metadata definition for the 'get_product' tool.

    name: "get_product",
    description: "Retrieve detailed information about a food product by its barcode",
    inputSchema: {
      type: "object",
      properties: {
        barcode: {
          type: "string",
          description: "The barcode/ID of the product (e.g., '3017620422003')",
        },
      },
      required: ["barcode"],
    },
  },

• src/index.ts:36-38 (registration)

  Registers the list tools handler which returns the tools array including 'get_product'.

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

• src/index.ts:45-46 (registration)

  Dispatches 'get_product' tool calls to the handleGetProduct method.

  case 'get_product':
    return await handlers.handleGetProduct(args.barcode);

• src/client.ts:42-54 (helper)

  Helper method in OpenFoodFactsClient that performs the actual API call to retrieve product data by barcode.

  async getProduct(barcode: string): Promise<ProductResponse> {
    await this.checkRateLimit('products');
    
    try {
      const response = await this.client.get(`/api/v2/product/${barcode}`);
      return ProductResponseSchema.parse(response.data);
    } catch (error) {
      if (axios.isAxiosError(error)) {
        throw new Error(`Failed to fetch product ${barcode}: ${error.response?.status} ${error.message}`);
      }
      throw error;
    }
  }