Which monitoring tool provides the ability to visualize the components of an application and the flow of API calls?

You can use AWS X-Ray to visualize the components of your application, identify performance bottlenecks, and troubleshoot requests that resulted in an error. Your Lambda functions send trace data to X-Ray, and X-Ray processes the data to generate a service map and searchable trace summaries. AWS X-Ray records how the Lambda functions are running. Use it to identify the call flow of your Lambda function and the performance of every API call within your application.