DeepSeek Harness Code Reuse Firewall Plugin

This plugin aims to prevent silent branching in AI-maintained codebases. It intervenes before code is written using deterministic retrieval—an IDF-weighted algorithm based on function names, docstrings, and other factors—to identify existing implementations and force the agent to reuse rather than duplicate them. It supports hash-lock detection and can be integrated into Auto_code_audit. It requires Python 3.10+, relies on name matching before code exists, does not support structural similarity detection, and requires the agent to make a manual decision about whether to reuse.