The video showcases the REA GitHub tool integrated with Claude Code, enabling AI agents to reverse engineer desktop applications by inspecting their shipped code, providing precise insights into features like clipboard handling in Electron apps such as Notion. It highlights successful case studies, limitations with native and server-side code, and emphasizes REA as a valuable, lawful tool for detailed app analysis and interoperability rather than full cloning.
The video explores how the REA (Reverse Engineer Anything) GitHub tool integrates with Claude Code to enable coding agents to analyze and explain features of desktop applications by inspecting the actual shipped code on a user’s machine. Using Notion as a case study, it reveals that when copying a block in Notion, the clipboard receives plain text and HTML with a hidden comment containing a Notion VC ID. Notion stores the real block data locally and uses this ID to restore blocks on paste. Since Notion’s desktop app is built on Electron, the web page cannot access the system clipboard directly and must send messages to the main process, a flow that REA helps trace precisely by pointing to exact code locations rather than relying on guesses.
REA works by letting an AI agent inspect the files, web bundles, and native instructions that an application ships, providing concrete evidence for how specific features operate. For example, in Notion, REA helped identify the minified communication channel and traced the clipboard write operation through four stages, confirming that only Notion’s own pages can write to the clipboard. This approach avoids speculation by showing the exact lines of code involved. However, when dealing with compiled native code, the process is more complex because decompiled code can be inaccurate. The agent must compare decompiled pseudo code with raw machine instructions and ask follow-up questions to resolve discrepancies.
The video highlights a detailed case study of reverse engineering the classic 1996 Windows game DX Ball. The agent used REA to analyze how the game calculates sound panning when a brick is hit. Initially, the decompiled code incorrectly showed the function as taking no inputs, but the machine instructions revealed it did take an input representing the brick’s horizontal position. By iteratively investigating, the agent reconstructed the correct function and verified it by comparing outputs with the original game across thousands of test cases. The project eventually rebuilt 270 functions exactly, producing a playable version of the game, demonstrating that full app reconstruction is possible but requires extensive verification.
The video also discusses the limitations and best use cases for REA. It works best with JavaScript desktop apps like those built on Electron because their shipped bundles are accessible without extra tools. Compiled programs require decompilers, which may be free or paid, and websites pose a challenge since server-side code never reaches the client machine. REA can only analyze code present on the user’s device, and all findings are subject to the user’s authorization and legal restrictions. The tool’s output is an inference that must be confirmed by observing the program’s runtime behavior, emphasizing that reverse engineering is a careful, iterative process.
In conclusion, the video recommends adding REA to Claude Code if you want detailed explanations of how specific features in desktop apps work by reading shipped code with exact references. It cautions that this is not a shortcut to cloning entire applications, especially those running on servers or with complex native code. Instead, REA is a powerful aid for lawful research and interoperability on software you own or are authorized to examine. The suggested next step is to set up REA, try it on a practice app, and then explore a feature in a desktop app you have permission to analyze, keeping in mind the need for thorough verification at every stage.
Useful Links
- REA (Reverse Engineer Anything) GitHub Repository — Directly enables the reverse engineering process described in the video, providing the tool used for inspecting shipped code and tracing application features.
- Claude Code AI Coding Agent — Central AI agent platform used with REA to perform code inspection and explanation tasks.