mcp-market-data

Instructions

Implementation Reference

• index.js:122-135 (handler)

  The `getMarketCap` function fetches top cryptocurrencies by market cap from the CoinGecko API.

  async function getMarketCap(limit = 20) {
    const data = await fetch(
      `https://api.coingecko.com/api/v3/coins/markets?vs_currency=usd&order=market_cap_desc&per_page=${limit}&page=1&sparkline=false`
    );
    return data.map((c, i) => ({
      rank: i + 1,
      symbol: c.symbol.toUpperCase(),
      name: c.name,
      price: c.current_price,
      market_cap: c.market_cap,
      volume_24h: c.total_volume,
      change_24h: c.price_change_percentage_24h,
    }));
  }

• index.js:273-281 (registration)

  The `market_cap` tool is defined in the `getToolDefinitions` method of the `MCPMarketServer` class.

    name: 'market_cap',
    description: 'Get top cryptocurrencies ranked by market cap with prices, volumes, and 24h changes.',
    inputSchema: {
      type: 'object',
      properties: {
        limit: { type: 'number', description: 'Number of coins to return (default: 20, max: 100)' }
      }
    }
  },

• index.js:329-330 (handler)

  The `handleToolCall` method handles the `market_cap` tool invocation by calling `getMarketCap`.

  case 'market_cap':
    return await getMarketCap(Math.min(args.limit || 20, 100));