list_variants

Instructions

Implementation Reference

• src/tools/variants.ts:270-317 (handler)

  The async handler that executes the list_variants tool logic: calls the Shopify GraphQL API with LIST_VARIANTS_QUERY, formats and returns product options and variants as text.

    async (args) => {
      const data = await client.graphql<{
        product:
          | {
              id: string;
              title: string;
              options: ProductOptionNode[];
              variants: {
                edges: Array<{ node: VariantNode }>;
                pageInfo: { hasNextPage: boolean };
              };
            }
          | null;
      }>(LIST_VARIANTS_QUERY, { productId: args.productId, first: args.first });
      if (!data.product) {
        return {
          content: [
            { type: "text" as const, text: `Product not found: ${args.productId}` },
          ],
        };
      }
      const p = data.product;
      const optionLines = p.options.map(
        (o) =>
          `  ${o.name} (#${o.position}): ${o.optionValues.map((v) => v.name).join(", ")}`,
      );
      const variantLines = p.variants.edges.map(({ node }) => formatVariant(node));
      return {
        content: [
          {
            type: "text" as const,
            text: [
              `${p.title} — ${p.id}`,
              "Options:",
              ...optionLines,
              `Variants (${p.variants.edges.length}):`,
              ...variantLines,
              p.variants.pageInfo.hasNextPage
                ? "(more variants available; raise `first` to page further)"
                : "",
            ]
              .filter(Boolean)
              .join("\n"),
          },
        ],
      };
    },
  );

• src/tools/variants.ts:193-196 (schema)

  Input schema for list_variants: productId (string GID) and first (int, 1-100, default 50).

  const listVariantsSchema = {
    productId: z.string().describe("Product GID."),
    first: z.number().int().min(1).max(100).default(50),
  };

• src/tools/variants.ts:266-317 (registration)

  Registration of the 'list_variants' tool on the McpServer inside registerVariantTools(), wired up in src/server.ts at line 64.

  server.tool(
    "list_variants",
    "List all variants of a single product, plus the product's option definitions (Size, Color, etc.) and possible values. For each variant returns: title, GID, price, compareAtPrice, SKU, barcode, current inventory quantity, taxable flag, inventory policy, and the option-value combination that produced it. Use to inspect a product's full SKU matrix before calling create_variants/update_variants/delete_variants.",
    listVariantsSchema,
    async (args) => {
      const data = await client.graphql<{
        product:
          | {
              id: string;
              title: string;
              options: ProductOptionNode[];
              variants: {
                edges: Array<{ node: VariantNode }>;
                pageInfo: { hasNextPage: boolean };
              };
            }
          | null;
      }>(LIST_VARIANTS_QUERY, { productId: args.productId, first: args.first });
      if (!data.product) {
        return {
          content: [
            { type: "text" as const, text: `Product not found: ${args.productId}` },
          ],
        };
      }
      const p = data.product;
      const optionLines = p.options.map(
        (o) =>
          `  ${o.name} (#${o.position}): ${o.optionValues.map((v) => v.name).join(", ")}`,
      );
      const variantLines = p.variants.edges.map(({ node }) => formatVariant(node));
      return {
        content: [
          {
            type: "text" as const,
            text: [
              `${p.title} — ${p.id}`,
              "Options:",
              ...optionLines,
              `Variants (${p.variants.edges.length}):`,
              ...variantLines,
              p.variants.pageInfo.hasNextPage
                ? "(more variants available; raise `first` to page further)"
                : "",
            ]
              .filter(Boolean)
              .join("\n"),
          },
        ],
      };
    },
  );

• src/tools/variants.ts:249-260 (helper)

  Helper function that formats a VariantNode into a human-readable string used in the list_variants handler output.

  function formatVariant(v: VariantNode): string {
    const opts =
      v.selectedOptions?.map((o) => `${o.name}=${o.value}`).join(", ") ??
      "(no options)";
    const sku = v.sku ? ` SKU:${v.sku}` : "";
    const cmp = v.compareAtPrice ? ` cmp:${v.compareAtPrice}` : "";
    const qty =
      v.inventoryQuantity !== null && v.inventoryQuantity !== undefined
        ? ` qty:${v.inventoryQuantity}`
        : "";
    return `  ${v.title} [${opts}] ${v.price}${cmp}${sku}${qty} — ${v.id}`;
  }

• src/tools/variants.ts:28-59 (helper)

  GraphQL query used by the list_variants tool to fetch product options and variants.

  const LIST_VARIANTS_QUERY = /* GraphQL */ `
    query ListVariants($productId: ID!, $first: Int!) {
      product(id: $productId) {
        id
        title
        options {
          id
          name
          position
          optionValues { id name hasVariants }
        }
        variants(first: $first) {
          edges {
            node {
              id
              title
              price
              compareAtPrice
              sku
              barcode
              position
              taxable
              inventoryPolicy
              inventoryQuantity
              selectedOptions { name value }
            }
          }
          pageInfo { hasNextPage endCursor }
        }
      }
    }
  `;