Show HN: ProxyBoy. A Windows HTTP/HTTPS debugging proxy with an AI assistant

ProxyBoy, a Windows-native HTTP/HTTPS debugging proxy with an AI assistant powered by GitHub Copilot, has been released as an experimental project. The tool captures, inspects, and modifies network traffic, offering features like GraphQL awareness, protobuf decoding, and breakpoint rules. It aims to provide a Windows alternative to tools like Proxyman with integrated AI capabilities.

A Windows-native HTTP/HTTPS debugging proxy with an AI-powered assistant, built with Electron. ⚠️ This is a personal/experimental project.If you need a mature, production-ready HTTP debugging proxy, go check out— it's excellent and was the direct inspiration for this project. ProxyBoy exists because I wanted a Windows-native alternative with agentic AI capabilities baked in, and I wanted to learn by building one. Proxyman ProxyBoy is a man-in-the-middle MITM HTTP/HTTPS proxy that captures, inspects, and modifies network traffic — similar to Charles Proxy, Fiddler, or Proxyman. What makes it different is the embedded AI assistant powered by the GitHub Copilot SDK https://github.com/features/copilot , which can analyze traffic, create rules, and help debug network issues conversationally. Traffic Capture — Intercept HTTP and HTTPS traffic with automatic SSL certificate generation Request/Response Inspector — View headers, bodies JSON, HTML, XML, images , timing, and metadata GraphQL Awareness — Detect GraphQL operations, show operation names, and filter traffic by operation Protobuf / gRPC Decoding — Decode protobuf payloads in the detail view with .proto files and fall back to raw field inspection when schemas are missing No Cache Toggle — Strip cache validators and return Cache-Control: no-store to force fresh responses Network Throttling — Simulate slower links with preset or custom upload, download, and latency profiles Request Composer — Build a request from scratch, send it through ProxyBoy, and inspect the captured result inline Upstream Proxy Chaining — Forward traffic through HTTP or SOCKS5 upstream proxies with bypass patterns and secure credential storage Cookie Inspector — Parse request cookies and Set-Cookie headers into a structured, searchable view AI Assistant — Chat panel powered by GitHub Copilot that can search traffic, analyze patterns, create rules, and export data Breakpoint Rules — Pause requests/responses mid-flight, inspect them, then forward or drop Map Local Rules — Serve local files instead of remote responses for mocking APIs Map Remote Rules — Forward matching requests to a different upstream host without changing your client Capture Rules — Switch between capture-all, allow-list, and block-list modes to control what gets recorded System Proxy Integration — Toggle Windows system proxy on/off from the app HAR Export/Import — Standard HAR format for sharing captures with other tools Configurable Columns — Show/hide columns, sort by any field, timestamps Body Search — Include request and response text bodies in traffic filtering when you need deeper search WebSocket and SSE Inspection — Capture live WebSocket frames and Server-Sent Events in the traffic detail view Script Rules — Run sandboxed JavaScript rules to rewrite requests and responses without leaving the app Copy as cURL — Right-click any request to copy it as a cURL command Keyboard Shortcuts — Fast access to proxy control, HAR import/export, filtering, and traffic actions Theme Modes — Dark, Light, or System theme selection with live switching Detachable AI Panel — Pop the assistant out into its own window HAR Import + Image Preview + AI Session Analysis Import a HAR file, preview images inline, and ask the AI assistant to break down what's in the capture. /pjperez/proxyboy/blob/master/assets/screenshot-har-import.png Content Type Filtering + JSON Body Viewer Filter traffic by content type JSON, HTML, CSS, JS, images, etc. and inspect formatted response bodies. /pjperez/proxyboy/blob/master/assets/screenshot-json-filter.png AI-Powered Request Analysis Select any request and ask the AI to explain it — it calls tools like /pjperez/proxyboy/blob/master/assets/screenshot-ai-analysis.png analyzeFlow to inspect headers, body, and context, then gives you a human-readable breakdown. The embedded Copilot agent has access to these tools: | Tool | Description | |---|---| getRecentTraffic | Fetch the latest captured flows | searchTraffic | Search flows by URL, body, or headers | getErrorFlows | Find all 4xx/5xx responses | getFlowDetails | Deep-dive into a specific request | createBreakpointRule | Create a breakpoint to pause matching traffic | createMapLocalRule | Mock an API endpoint with a local file | exportHar | Export captured traffic as HAR | controlProxy | Start or stop the proxy engine | Tool execution can be auto-approved or require manual confirmation per-call. Electron + React + TypeScript — MITM proxy engine http-mitm-proxy https://github.com/joeferner/node-http-mitm-proxy — AI agent capabilities @github/copilot-sdk https://github.com/features/copilot — SQLite in-process for persistence sql.js https://github.com/sql-js/sql.js — Styling Tailwind CSS https://tailwindcss.com/ — Virtualized traffic list react-virtuoso https://virtuoso.dev/ Electron Forge — Build and packaging Windows 10/11 Node.js 20+ GitHub Copilot subscription for the AI assistant — the proxy works without it git clone https://github.com/pjperez/proxyboy.git cd proxyboy npm install npm start npm run build Output goes to out/make/ . Start the proxy — Click the play button in the status bar or use the AI assistant Route traffic — Either toggle "System Proxy" in settings, or manually configure your browser/app to use 127.0.0.1:9090 Inspect — Click any row to see request/response details Create rules — Use the Breakpoints, Map Local, or Map Remote views, or ask the AI assistant AI Assistant — Click the robot icon in the sidebar or press Ctrl+Shift+A To inspect HTTPS traffic, you'll need to trust ProxyBoy's root CA certificate: - Go to Settings → Install Certificate - This installs a local root CA into the Windows certificate store - Restart your browser after installing The certificate is generated locally and stored in your user profile. It never leaves your machine. If a request fails immediately after TLS setup and ProxyBoy tags it as ssl-pinning-suspected , the target app is probably rejecting the ProxyBoy MITM certificate instead of accepting your locally trusted CA. Common approaches: Android debug builds — Use a debug-only network security config or a test build that trusts user-installed CAs. iOS simulators — Prefer development builds with pinning disabled, or use instrumentation tools in local test environments. Desktop apps / Electron apps — Check for developer flags, debug certificates, or test-only trust overrides before trying to intercept production builds. ProxyBoy can only point out the likely cause. Certificate pinning bypasses are app-specific, and the safest path is usually a debug/test build with relaxed certificate validation. src/ ├── main/ Electron main process │ ├── proxy/ MITM proxy engine, interceptor, certificate manager │ ├── agent/ Copilot SDK client, tools, prompts │ ├── ipc/ IPC handlers between main ↔ renderer │ ├── storage/ SQLite database, queries │ └── utils/ Windows proxy settings, HAR export ├── renderer/ React UI │ ├── components/ Traffic list, detail view, agent panel, rules editors │ ├── stores/ Zustand state management │ └── utils/ cURL generation, helpers └── shared/ Types, constants shared between main & renderer Windows only — System proxy integration uses Windows registry; the rest could theoretically work cross-platform No request/response editing in breakpoints — You can inspect and forward/drop, but not modify yet SSL inspection quirks — Some sites with certificate pinning or HSTS preload may not work through the proxy Cloudflare challenges — Sites behind Cloudflare browser challenges will typically fail through any MITM proxy Very limited automated tests — There is a small test foothold now, but coverage is still far from production-ready 🙃 — The primary inspiration. Seriously, go use Proxyman if you want a polished, reliable proxy tool. It's great. Proxyman https://proxyman.io/ and Charles Proxy https://www.charlesproxy.com/ — Other excellent tools in this space Fiddler https://www.telerik.com/fiddler — Powers the AI assistant, and also helped build this entire app GitHub Copilot https://github.com/features/copilot MIT — Do whatever you want with it.