AI-Native
Web Traffic Debugging Tool
A professional-grade, AI-native network debugging tool built with Tauri, React, and Rust. A high-performance mitmproxy engine inspects HTTP/HTTPS, WebSocket, SSE, and gRPC traffic locally — with deep AI integration, a built-in MCP server, and a plugin & theme platform.
Built-in MCP Support
Bridge the gap between your network traffic and AI agents. RelayCraft ships a built-in Model Context Protocol server that any MCP-compatible client can connect to.
Live Traffic Context
Let Claude, Cursor, or any MCP client read live sessions, search flows, and understand API behavior instantly.
Agent-Driven Debugging
Empower your AI to create and manage rules, replay requests, and inspect traffic — with full visibility into external AI tool activity.
Powerful Features for
Modern Development
Intercept, map, analyze, modify — a unified hub for all your network requests.
Traffic Monitor
High-performance, fully-local traffic capture powered by mitmproxy. Inspect HTTP/1.1, HTTP/2, WebSocket, Server-Sent Events, and gRPC unary calls with deep detail views, image previews, and syntax highlighting.
Rules Engine
Manage traffic behavior with a visual rule builder — no config files needed. Supports 6 rule types, reusable templates, and portable rule files for team sharing.
AI Assistant
AI-native throughout the entire workflow. Global Ctrl(⌘) + K command center understands your intent and acts as your co-debugger.
Breakpoints
Real-time pause, edit, and resume requests/responses. Supports path matching or regex matching, request or response interception — perfect for security testing and edge case simulation.
Request Composer
Built-in API client designed for debugging. Edit and resend any captured request — including WebSocket messages — or import cURL in one click.
Python Scripting
Natively supports the full mitmproxy Python ecosystem. Write powerful custom logics for complex scenarios beyond visual rules.
Extensibility
An advanced, open platform for plugins and themes. Extend functionality with the plugin system and restyle the interface from the community theme market — build your perfect tool.
Security & Privacy: Your data, only yours
Fully Offline
No internet required. Your traffic data never leaves your device.
Zero Accounts
No registration, no login, no subscriptions. Just download and use.
Local Storage
All rules, configs, and captures 100% stored locally, fully under your control.
Local AI Support
Support for Ollama and other local LLMs — sensitive data never goes to cloud.
Open Source
Core code GPLv3 open source (dual-licensed for commercial use), verified by the community, no backdoors.
No Telemetry
Reject all forms of invisible data collection, analysis, or tracking.
Sandboxed Plugins
Plugins declare explicit permissions and run within enforced storage quotas. Nothing is installed silently.
Who is using RelayCraft?
Web Frontend Devs
Mock APIs, debug network requests, and solve CORS instantly with visual rules.
Mobile Developers
Capture traffic from any device, simulate weak networks, and debug API calls.
QA Engineers
Easily simulate edge cases, verify interfaces, and reproduce complex issues.
Security Researchers
Request tampering, vulnerability analysis, and in-depth protocol research.
Start Debugging in Minutes
Download RelayCraft for your preferred operating system. Free for personal use.
For complete assets and release notes, visit the GitHub Releases page. You can verify file integrity with SHA256 checksums.