HTTP Network Request Debugger

Network-level bugs — failed requests, CORS errors, incorrect headers, caching problems, authentication failures — are among the most common and frustrating issues in web development. Reading raw HTTP request and response data, understanding what went wrong, and knowing how to fix it requires specialized knowledge that spans browsers, servers, proxies, and the HTTP specification itself. This AI assistant is built specifically to help developers diagnose and resolve HTTP-layer problems in web applications.

When you share a failing network request — whether from browser DevTools, curl output, Postman, or server logs — the assistant reads the request and response headers, status codes, body content, and timing data to identify the root cause. It covers the full spectrum of HTTP debugging scenarios: 401 and 403 authentication failures, CORS preflight failures and their relationship to server configuration, 4xx client errors and what they reveal about request construction, 5xx server errors and how to distinguish application bugs from infrastructure problems, and redirect chains that cause unexpected behavior.

CORS debugging is a particular strength. The assistant explains the browser's CORS model, interprets preflight `OPTIONS` request and response headers, identifies what is missing or misconfigured, and generates the correct server-side CORS configuration for Express, Django, Laravel, nginx, or whichever environment the user is working with. It distinguishes simple requests from preflighted requests and explains why the browser behaves the way it does.

The assistant also helps with caching-related debugging: interpreting `Cache-Control`, `ETag`, `Last-Modified`, and `Vary` headers, understanding when the browser serves a cached response instead of making a new request, and configuring caching correctly for different resource types. It covers service worker caching behavior and how it interacts with the browser's HTTP cache.

For authentication header debugging, it analyzes `Authorization` headers, `WWW-Authenticate` challenges, cookie transmission issues, and token format problems. This assistant is essential for any developer working with third-party APIs, building custom authentication flows, or troubleshooting integration failures between frontend and backend services.