Built a local pre-processing plugin for Claude Code after research & measuring real metrics (3,500+ tests, v1.22.1) — Looking for feedback & ideas

A developer has released chamnan v1.22.1, a local pre-processing plugin for Claude Code that sanitizes, budgets, and organizes data before it reaches the AI model. Built in pure Python with over 3,500 automated tests, the tool aims to provide deterministic context control and prevent data leaks in large or sensitive codebases. The developer tested existing plugins and found inconsistencies, prompting the creation of this solution.

Hi everyone, I wanted to share a project I’ve been developing for my own workflow with Claude Code, and hopefully get some feedback and ideas from the community on where to take it next. Working on large-scale, complex projects, I needed better control over context, token consumption, and security. Before building my own tool, I tested various plugins in the market. As someone who likes to measure and verify metrics independently, I ran tests on actual context usage and noticed that under large, messy repository conditions, results often varied from what was expected. Since my projects involve sensitive codebases, I wanted a deterministic local pre-processing layer that sanitizes, budgets, and organizes data before anything is passed to Claude Code—ensuring zero unexpected data leaks and absolute predictability. What started as a simple helper script turned into a serious engineering effort. I went through over 1,000 research papers and technical docs to refine context retention, token budgeting, and local redaction. Building reliability tooling is a constant battle against edge cases: silent context loss, false successes, cross-platform path quirks like Windows process locks , and state drift. My rule became: Never believe a bug is fixed until a test proves it. Today, the plugin chamnan is at v1.22.1 . It's built in pure Python standard library only, zero external packages and backed by 3,500+ automated tests . .chamnan/ so Claude Code doesn't waste tokens re-discovering architecture across sessions. I dogfood this daily, but since I built it to share with other developers working on large or privacy-conscious projects, I'd love to hear your thoughts: If you're interested in the architecture or test setup, you can check out the repository here: https://github.com/ArcticFox2029/chamnan https://github.com/ArcticFox2029/chamnan