ShipStation API MCP Server

Implementation Reference

• src/tools/carrier-tools.js:29-41 (handler)

  The MCP tool handler that fetches carrier packages using shipStationClient.getCarrierPackages and returns formatted JSON response or error.

  handler: async ({ carrierCode }) => {
    try {
      const packages = await shipStationClient.getCarrierPackages(carrierCode);
      return {
        content: [{ type: "text", text: JSON.stringify(packages, null, 2) }]
      };
    } catch (error) {
      return {
        content: [{ type: "text", text: error.message }],
        isError: true
      };
    }
  }

• src/tools/carrier-tools.js:26-28 (schema)

  Zod input schema defining the required 'carrierCode' string parameter.

  schema: {
    carrierCode: z.string().describe("Carrier code (e.g., 'ups', 'fedex', 'usps')")
  },

• src/server.js:184-191 (registration)

  Registration loop that dynamically registers all tools (including 'list_carrier_packages') with the MCP server using server.tool(name, schema, handler).

  ].forEach(tool => {
    server.tool(
      tool.name,
      tool.schema,
      tool.handler,
      { description: tool.description }
    );
  });

• src/api-client.js:106-108 (helper)

  ShipStationClient helper method that performs the API GET request to retrieve packages for the specified carrier.

  async getCarrierPackages(carrierCode) {
    return this.request('GET', '/carriers/listpackages', null, { carrierCode });
  }