Crypto Price & Market Analysis MCP Server

Instructions

Implementation Reference

• src/tools/price.ts:9-48 (handler)

  The handler function that executes the get-crypto-price tool logic: parses input symbol, fetches assets from CoinCap, finds the asset, formats price info, handles errors.

  export async function handleGetPrice(args: unknown) {
    const { symbol } = GetPriceArgumentsSchema.parse(args);
    const upperSymbol = symbol.toUpperCase();
  
    try {
      const assetsData = await getAssets();
      
      if (!assetsData) {
        return {
          content: [{ type: "text", text: "Failed to retrieve cryptocurrency data" }],
        };
      }
      
      const asset = assetsData.data.find(
        (a: { symbol: string; }) => a.symbol.toUpperCase() === upperSymbol
      );
  
      if (!asset) {
        return {
          content: [
            {
              type: "text",
              text: `Could not find cryptocurrency with symbol ${upperSymbol}`,
            },
          ],
        };
      }
  
      return {
        content: [{ type: "text", text: formatPriceInfo(asset) }],
      };
    } catch (error) {
      return {
        content: [{ 
          type: "text", 
          text: error instanceof Error ? error.message : `Failed to retrieve cryptocurrency data: ${String(error)}` 
        }],
      };
    }
  }

• src/tools/price.ts:5-7 (schema)

  Zod input schema defining the 'symbol' parameter for the tool.

  export const GetPriceArgumentsSchema = z.object({
    symbol: z.string().min(1),
  });

• src/index.ts:38-49 (registration)

  Registers the 'get-crypto-price' tool on the MCP server with title, description, input schema, and handler.

  server.registerTool(
    "get-crypto-price",
    {
      title: "Get Crypto Price",
      description: "Get current price and 24h stats for a cryptocurrency",
      inputSchema: GetPriceArgumentsSchema.shape,
    },
    async (args, _extra) => {
      const result = await handleGetPrice(args);
      return result as any;
    }
  );