Who Wrote This Line? New Tool Traces Every Edit Back to Human or AI
Human vs. AI – Diff-based line-level provenance for text under agentic editing
A new open-source tool, us-vs-them, determines whether each line of a text was written by a human or an AI agent, using only version history—no markup required. It's designed for agentic coding and editing, where preserving human-authored code is crucial. The tool outputs 'islands' of human-authored lines within a 'sea' of machine-generated text, with scores indicating the degree of human authorship. It works as a library or CLI tool and can be used in any git repository.
Text a human wrote or edited should be considered close to sacred: an agent should be hesitant and have a very good reason to touch it.