mcp-drizly

Instructions

Implementation Reference

• src/index.ts:409-435 (handler)

  MCP tool handler for 'add_to_cart' - validates input using AddToCartSchema, creates a DrizlyCartItem object, calls the addToCart method, and returns a JSON response with success message and updated cart

  case "add_to_cart": {
    const params = AddToCartSchema.parse(args);
    const cartItem: DrizlyCartItem = {
      productId: params.productId,
      name: params.name,
      quantity: params.quantity,
      price: params.price,
      imageUrl: params.imageUrl,
    };
    const cart = drizly.addToCart(cartItem);
  
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify(
            {
              message: `Added ${params.quantity}x ${params.name} to cart`,
              cart,
            },
            null,
            2
          ),
        },
      ],
    };
  }

• src/browser.ts:401-412 (handler)

  Core business logic implementation - adds item to cart or increments quantity if already exists, recalculates cart totals, returns updated cart state

  addToCart(product: DrizlyCartItem): DrizlyCart {
    const existingIndex = this.cart.items.findIndex((i) => i.productId === product.productId);
  
    if (existingIndex >= 0) {
      this.cart.items[existingIndex].quantity += product.quantity;
    } else {
      this.cart.items.push({ ...product });
    }
  
    this.recalculateCart();
    return this.cart;
  }

• src/index.ts:56-62 (schema)

  Zod schema definition for validating add_to_cart tool input parameters - requires productId, name, quantity (min 1), and price; imageUrl is optional

  const AddToCartSchema = z.object({
    productId: z.string().describe("Product ID to add to cart"),
    name: z.string().describe("Product name"),
    quantity: z.number().int().min(1).describe("Quantity to add"),
    price: z.number().describe("Price per unit"),
    imageUrl: z.string().optional().describe("Product image URL"),
  });

• src/browser.ts:32-38 (schema)

  TypeScript interface defining the structure of a cart item used by the addToCart implementation

  export interface DrizlyCartItem {
    productId: string;
    name: string;
    quantity: number;
    price: number;
    imageUrl?: string;
  }

• src/index.ts:175-189 (registration)

  MCP tool registration - defines the tool name, description, and JSON Schema for input validation in the ListToolsRequestSchema handler

  {
    name: "add_to_cart",
    description: "Add a product to the shopping cart",
    inputSchema: {
      type: "object",
      properties: {
        productId: { type: "string", description: "Product ID to add" },
        name: { type: "string", description: "Product name" },
        quantity: { type: "number", description: "Quantity to add (minimum 1)" },
        price: { type: "number", description: "Price per unit" },
        imageUrl: { type: "string", description: "Product image URL (optional)" },
      },
      required: ["productId", "name", "quantity", "price"],
    },
  },