Network Overrides API (DevTools)

Debugging tool that intercepts and overrides network API responses from DevTools panel or popup. For developers only.

Network Overrides API is a developer tool for intercepting and modifying network requests directly from Chrome DevTools or the extension popup. Use it to reproduce API states and edge cases without changing your backend or frontend code. Key features: • Capture Fetch, XHR, GraphQL, document, script, stylesheet, and image requests • Override JSON, text, image, or raw base64 response bodies • Change HTTP status codes and response headers • Add or replace request headers, including Authorization • Simulate realistic response delays • Redirect matching requests with wildcard substitution • Simulate network failures such as timeout, connection refused, DNS failure, and offline mode • Match requests by URL substring, wildcard, regular expression, HTTP method, or GraphQL operation • Enable, disable, duplicate, import, and export override rules • Organize rules into reusable profiles • Store rules separately for each domain • Use the same interface from the toolbar popup or Chrome DevTools panel Network Overrides API uses the Chrome debugger permission only while interception is enabled for the active tab. All override rules and captured request data remain locally on the user's device. The extension does not include analytics, advertising, or tracking. Category: Developer Tools Single purpose: Allow developers to capture, intercept, and locally override network requests and responses for debugging and testing. ## Permission justifications debugger: Required to attach to the active tab through the Chrome DevTools Protocol, pause matching requests, and apply mocked responses, redirects, headers, delays, or network failures. The debugger is used only when the user enables interception. storage: Required to save per-domain override rules, profiles, UI preferences, and temporary interception state so the extension continues working across DevTools sessions and browser restarts. Host permission <all_urls>: Required because developers may debug applications and APIs hosted on any domain. Access is used only for the active tab selected by the user while network interception is enabled. Remote code: No. All executable code is included in the extension package. Data usage: The extension processes request URLs, headers, request bodies, and response bodies locally to provide debugging features. Rules are stored in chrome.storage.local, while temporary session data is stored in chrome.storage.session. No user data is transmitted to the developer's servers, sold, or used for advertising.