Marketplace Search MCP

Instructions

Implementation Reference

• src/index.ts:190-224 (handler)

  The registration and handler implementation for the psa_population_report tool. It defines the parameters (certNumber, specID) and fetches data from a backend URL.

  server.tool(
    "psa_population_report",
    "Look up PSA card certification details and full population report. Returns card info (year, brand, subject, grade) and complete grade breakdown from Auth through PSA 10, showing how many cards exist at each grade level.",
    {
      certNumber: z
        .string()
        .optional()
        .describe('PSA certification number printed on the slab (e.g. "10000001")'),
      specID: z
        .number()
        .int()
        .optional()
        .describe("PSA spec ID for direct population lookup (advanced, from cert lookup)"),
    },
    async ({ certNumber, specID }) => {
      const params = new URLSearchParams();
      if (certNumber) params.set("certNumber", certNumber);
      if (specID) params.set("specID", String(specID));
  
      const url = `${BACKEND_URL}/psa/pop?${params.toString()}`;
      const res = await fetch(url);
      const data = await res.json();
  
      if (!data.success) {
        return {
          isError: true,
          content: [{ type: "text", text: `Error: ${data.error}` }],
        };
      }
  
      return {
        content: [{ type: "text", text: JSON.stringify(data, null, 2) }],
      };
    }
  );