Reading the network tab without losing your mind
DevTools shows you everything, which is the problem. Here's how I filter signal from noise when reverse-engineering a web application's API.
Open DevTools on any modern web app and you'll see hundreds of network requests. Most of them are noise: analytics, fonts, prefetch, third-party widgets. The actual API calls you care about are usually a small fraction.
Here's the workflow I use to cut through the noise consistently.
Filter aggressively, early
Before doing anything in the app, set your network tab filter to Fetch/XHR. That alone removes 80% of the noise. You only care about JSON-ish API calls, not images or scripts.
Use the "Initiator" column
The Initiator column tells you which script triggered the request. Group by initiator and you'll see the API calls grouped by the component that fired them — login form, dashboard, settings page. Way more useful than chronological order.
Save the HAR file before you forget
Right click → Save all as HAR with content. This gives you a full replayable session. Worth it every single time. I've come back to HAR files months later when I needed to remember exactly what sequence of calls produced a specific behavior.
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