get-stock-data

Implementation Reference

• src/index.ts:64-83 (handler)

  The MCP tool handler function for 'get-stock-data'. It receives input parameters, calls the getStockData helper, formats the response as MCP content, and handles errors.

  async ({ symbol, interval = '5min', outputsize = 'compact' }) => {
    try {
      const data = await getStockData(symbol, interval, outputsize);
      return {
        content: [{ type: 'text', text: data }],
      };
    } catch (error) {
      return {
        content: [
          {
            type: 'text',
            text: `Error fetching stock data: ${
              error instanceof Error ? error.message : String(error)
            }`,
          },
        ],
        isError: true,
      };
    }
  },

• src/index.ts:51-63 (schema)

  Zod schema for input validation of the 'get-stock-data' tool: symbol (string), interval (optional enum), outputsize (optional enum).

  {
    symbol: z.string().describe('Stock symbol (e.g., IBM, AAPL)'),
    interval: z
      .enum(['1min', '5min', '15min', '30min', '60min'])
      .optional()
      .describe('Time interval between data points (default: 5min)'),
    outputsize: z
      .enum(['compact', 'full'])
      .optional()
      .describe(
        'Amount of data to return (compact: latest 100 data points, full: up to 20 years of data)',
      ),
  },

• src/index.ts:49-84 (registration)

  Registration of the 'get-stock-data' tool on the MCP server, including schema and handler function.

  server.tool(
    'get-stock-data',
    {
      symbol: z.string().describe('Stock symbol (e.g., IBM, AAPL)'),
      interval: z
        .enum(['1min', '5min', '15min', '30min', '60min'])
        .optional()
        .describe('Time interval between data points (default: 5min)'),
      outputsize: z
        .enum(['compact', 'full'])
        .optional()
        .describe(
          'Amount of data to return (compact: latest 100 data points, full: up to 20 years of data)',
        ),
    },
    async ({ symbol, interval = '5min', outputsize = 'compact' }) => {
      try {
        const data = await getStockData(symbol, interval, outputsize);
        return {
          content: [{ type: 'text', text: data }],
        };
      } catch (error) {
        return {
          content: [
            {
              type: 'text',
              text: `Error fetching stock data: ${
                error instanceof Error ? error.message : String(error)
              }`,
            },
          ],
          isError: true,
        };
      }
    },
  );

• src/alphaVantage.ts:21-68 (helper)

  Core helper function getStockData that fetches intraday or daily stock data from Alpha Vantage API using axios, handles daily vs intraday endpoints, extracts time series, and formats using formatTimeSeriesData.

  export async function getStockData(symbol: string | string[], interval: string | string[] | 'daily', outputsize: string = 'compact'): Promise<string> {
      try {
          // Ensure parameters are strings, not arrays
          const symbolStr = Array.isArray(symbol) ? symbol[0] : symbol;
          const intervalStr = Array.isArray(interval) ? interval[0] : interval;
          const outputsizeStr = Array.isArray(outputsize) ? outputsize[0] : outputsize;
  
          let url: string;
          let timeSeriesKey: string;
  
          if (intervalStr === 'daily') {
              // Use TIME_SERIES_DAILY endpoint
              url = `${BASE_URL}?function=TIME_SERIES_DAILY&symbol=${symbolStr}&outputsize=${outputsizeStr}&apikey=${API_KEY}`;
              timeSeriesKey = 'Time Series (Daily)';
          } else {
              // Use TIME_SERIES_INTRADAY endpoint
              url = `${BASE_URL}?function=TIME_SERIES_INTRADAY&symbol=${symbolStr}&interval=${intervalStr}&outputsize=${outputsizeStr}&apikey=${API_KEY}`;
              timeSeriesKey = `Time Series (${intervalStr})`;
          }
  
          const response = await axios.get(url);
  
          // Check for error messages from Alpha Vantage
          if (response.data['Error Message']) {
              throw new Error(response.data['Error Message']);
          }
  
          if (response.data['Note']) {
              console.warn('API Usage Note:', response.data['Note']);
          }
  
          // Extract the time series data
          const timeSeries = response.data[timeSeriesKey];
  
          if (!timeSeries) {
              throw new Error('No time series data found in the response');
          }
  
          // Format the data
          const formattedData = formatTimeSeriesData(timeSeries, symbolStr, intervalStr);
          return formattedData;
      } catch (error) {
          if (axios.isAxiosError(error)) {
              throw new Error(`API request failed: ${error.message}`);
          }
          throw error;
      }
  }

• src/alphaVantage.ts:73-96 (helper)

  Helper function to format the raw time series data from Alpha Vantage into a readable string, showing OHLCV for the most recent 10 data points.

  function formatTimeSeriesData(timeSeries: any, symbol: string, interval: string | 'daily'): string {
      const dates = Object.keys(timeSeries).sort().reverse(); // Most recent first
  
      let result = `Stock data for ${symbol.toUpperCase()} (${interval === 'daily' ? 'Daily' : interval} intervals):\n\n`;
  
      // Limit to 10 data points to avoid overwhelming responses
      const limitedDates = dates.slice(0, 10);
  
      for (const date of limitedDates) {
          const data = timeSeries[date];
          result += `${date}:\n`;
          result += `  Open: ${data['1. open']}\n`;
          result += `  High: ${data['2. high']}\n`;
          result += `  Low: ${data['3. low']}\n`;
          result += `  Close: ${data['4. close']}\n`;
          result += `  Volume: ${data['5. volume']}\n\n`;
      }
  
      if (dates.length > 10) {
          result += `... and ${dates.length - 10} more data points available.\n`;
      }
  
      return result;
  }