Insane Ways To Actually Use GitHub's #1 Trending Repo REA

Highlights

• Reverse Engineer Anything is an MCP server that connects to AI coding agents like Claude Code to inspect browser requests and website code.

• The tool labels every finding as seen, guessed, or unknown using captured evidence like network requests and executed code.

• Running the tool on a demo billing app revealed a discrepancy where two accounts saw one price on screen but were charged a different amount.

• Testing uncovered server vulnerabilities allowing negative seat numbers to be accepted and customer data to be accessed without backend authorization.

• The tool detects layout errors on mobile devices, such as dashboard headers extending past the edge of the screen.

Timeline

1. 00:00 - 04:23

   Core mechanism and setup of the tool

   AI agents often struggle to understand complex app behavior because standard tools only analyze screenshots and surface descriptions. This tool fills that gap by tracking interactions back to the precise code sending requests to the server. It logs requests and responses as verifiable evidence, preventing the agent from passing off unverified guesses as facts. Desktop apps are supported if they are built like websites or store program files locally. Running the install script configures the skill globally across all Claude Code sessions.

   • Reverse Engineer Anything is an MCP server designed to let AI agents dig into web applications and desktop apps.
   • Traditional browser testing tools rely on screenshots and miss background server requests, while this tool tracks data sent and received.
   • Every finding is categorized as seen, guessed, or unknown based on captured proof and evidence IDs.
   • Installation involves running a terminal command from the GitHub repository that detects coding tools and adds the reverse engineering skill.
2. 04:24 - 07:20

   Importing features and researching competitors

   Developers use the tool to analyze loved features in other applications and rebuild them in their own projects. When prompted to analyze Obsidian and Notion, the agent generates a behavior list explaining how components operate under various user interactions. This goes beyond static design by capturing dynamic logic, such as how deleted nodes handle broken links. Similarly, auditing an entire group of competitor applications reveals unadvertised capabilities buried in pre-login code assets.

   • The tool maps out features from established apps like Obsidian and Notion to replicate them in custom software.
   • Captured behavior lists detail precise mechanics like node positioning, link drawing, and interaction responses.
   • Running the tool across multiple competitors uncovers hidden features loaded during sign-in that are never mentioned on public websites.
3. 07:21 - 10:17

   Auditing features and finding bugs

   Testing features dynamically through the browser rather than scanning source files uncovers edge-case failures. In a demo application test, the tool discovered that two accounts were charged incorrect amounts despite the interface showing correct line items. The investigation traced the failure to the final addition step in the calculation. Further analysis exposed server-side flaws, including accepting negative seat allocations and failing to generate billing logs for invoices.

   • Running the tool on a custom app without reading the code exposes runtime errors missed by standard code reviews.
   • Testing discovered a billing bug where displayed prices matched rules, but final checkout charges were incorrect for specific accounts.
   • Additional security logic gaps allowed servers to accept negative seat counts and omit records from billing logs.
4. 10:18 - 12:12

   Performance checks and security audits

   Full-site performance scans identify layout anomalies, such as mobile dashboard headers overflowing past screen boundaries. Prior to publishing, security audits check applications for leaks of sensitive credentials and configuration data. The scanning process locates exposed API keys and unauthenticated endpoints that expose private customer records, sorting the discoveries by severity and providing recommended fixes.

   • Automated site-wide checks evaluate overall site speed, broken links, and layout rendering issues across devices.
   • Security scans identify exposed API keys for services like OpenAI and Stripe.
   • The tool flags logic flaws that grant unauthorized users access to customer data without backend authentication.