Observing Core Web Vitals with OpenTelemetry

Core Web Vitals (CWV) are essential metrics used by Google to assess the quality of user experience on web pages, focusing on loading performance, interactivity, and visual stability through metrics like Largest Contentful Paint (LCP), First Input Delay (FID), and Cumulative Layout Shift (CLS). These metrics are crucial for identifying performance gaps and are influential in Google's page ranking system, making them important for SEO. The text explains how to use OpenTelemetry to instrument browser applications and send CWV data to Honeycomb, enabling detailed analysis and monitoring. It outlines setting up instrumentation with OpenTelemetry, including installing necessary packages and creating a custom instrumentation class to capture CWV data. Additionally, it describes querying CWV data in Honeycomb to establish baseline queries and monitor the 75th percentile of page loads, allowing for the identification of anomalies and improvement areas, particularly focusing on LCP values. By examining attributes such as screen size and browser properties, users can uncover patterns and make targeted improvements to enhance web page performance and user experience.