# How I Built a Local Tool That Maps Any Codebase in 55 Seconds No Cloud, No Uploads

> Source: <https://dev.to/ntooxx/how-i-built-a-local-tool-that-maps-any-codebase-in-55-seconds-no-cloud-no-uploads-48na>
> Published: 2026-06-18 15:00:15+00:00

I spend a lot of time working with AI coding agents Claude Code, Cline, Cursor, OpenCode. And every time I start a new task in a large repo, I hit the same wall: the agent has no idea what the codebase looks like.

So I built Sentinel.

Point it at any repo. It scans everything locally (no uploads, no API keys, no internet needed) and produces:

Every scan runs entirely on your machine. No code leaves your disk. No API calls. Pure Python stdlib — zero external dependencies.

The AI agent prompt it generates a total of (~2,500 tokens) replaces hours of manually reading files and explaining the codebase to your agent.

```
bash
pip install git+https://github.com/Ntooxx/Sentinel.git
project-sentinel scan . --fast
🔗 GitHub: https://github.com/Ntooxx/Sentinel
🌐 Dashboard demo: sentinel-nt.netlify.app
📦 197 tests, 0 failures
Let me know what breaks or what's missing. I'm actively improving it.
```