HTTP Proxy Rules Manager

About

TTP Proxy Rules Manager
  
  Intercept and rewrite HTTP/HTTPS traffic locally. Manage proxy rules from your browser — no Charles, no Proxyman, no fuss.

  What it does

  HTTP Proxy Rules Manager runs a local proxy on your machine and gives you a browser popup to control it. Create rules that match
  URLs and HTTP methods, then rewrite requests or responses in real time — without touching your app's source code.

  Use cases

  - Test how your frontend handles different API responses without changing the backend
  - Inject or override response headers during development
  - Simulate error states (404, 500, 429) for specific endpoints
  - Replace response bodies to mock data mid-session
  - Count how many times a rule fires and auto-disable it after N uses

  Features

  - Match by URL (exact or regex) and HTTP method
  - Rewrite request body, response body, or both
  - Inject, modify, or remove headers
  - Override HTTP status codes
  - Count-limited rules — auto-disable after a set number of uses
  - Enable/disable individual rules without deleting them
  - All rules persist across sessions

  Privacy

  Everything runs on your own machine. The extension communicates only with a local proxy at 127.0.0.1 — no data leaves your computer,
  no analytics, no telemetry.

  Setup
  
  The extension requires a one-time native host installation (Python 3 required). An installer script is generated and downloaded
  directly from the popup — no manual file editing needed.

  During installation, a local Certificate Authority (CA) certificate is generated on your machine. This certificate is automatically
  added to your macOS login keychain so that Chrome trusts the proxy's TLS connections. Without it, HTTPS traffic cannot be
  intercepted. You can remove the certificate from Keychain Access at any time to uninstall.

  Supported platforms: macOS