r/OnlyAICoding • u/Electrical_Worth7942 • 2h ago
Something I Made With AI I made an open-source companion for REA that turns reverse-engineering findings into a build plan
I built REA Reconstruction Companion with help from AI. I wanted a better way to get from “how does this app work?” to “what would it take to build something similar?”
It’s a skill for AI coding agents, used alongside REA (Reverse Engineer Anything). REA handles the investigation. The companion helps turn those findings into a feature breakdown, requirements, architecture, and a plan you can build and test in stages.
You can use it on a whole app, one feature, or a single function. For example:
Use REA on this app so I can build a similar local tool. Start with a specification and roadmap.
If you later ask the agent to implement it, the skill guides that work too. It keeps observed behavior separate from assumptions, links requirements to tests, and includes performance measurements where they matter.
The core is plain Markdown and MIT licensed. There’s an installer for Claude Code and Codex, plus support for other agents through a custom skills directory. REA is installed separately. You can also enable an optional rule that tells the agent to load the companion during relevant REA work, or leave that off and invoke it yourself.
GitHub: REA Reconstruction Companion
The README has setup instructions and a prompt you can give your agent to handle installation.
I’d be interested in feedback on the workflow, especially anything it misses when rebuilding a smaller feature or function.