Reverse Engineer Anything plugs into AI coding agents like Claude Code, Codex, Cursor and Gemini CLI, and gives them the tools to look inside an app and figure out what it’s actually doing, even when you don’t have the source code. You ask in plain English, something like “why does this app’s search work the way it does?”, and the agent uses REA to dig through native binaries, Electron and JavaScript apps, .NET assemblies or websites, then comes back with an explanation and the evidence behind it. From there it can help you rebuild the feature in your own project.
The guided Notes example on the website is a good first project, and it’s worth keeping REA updated since it changes fast. REA is free and open source under the MIT license, and the analysis runs locally on your machine, though your agent’s model provider still sees the results it receives. Deeper native analysis needs Hopper, Ghidra or IDA, and some of those are paid tools you’ll need your own licence for. Because it’s built for lawful research, learning, interoperability and analysing software you own or are authorised to examine, keep your use within those limits.
