raphaelchristi/harness-evolver
14 stars · Last commit 2026-04-18
Automated harness evolution for AI agents. A Claude Code plugin that iteratively optimizes system prompts, routing, retrieval, and orchestration code using full-trace counterfactual diagnosis. Based on Meta-Harness (Lee et al., 2026).
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<p align="center"> <img src="assets/banner.jpg" alt="Harness Evolver" width="100%"> </p> # Harness Evolver <p align="center"> <a href="https://www.npmjs.com/package/harness-evolver"><img src="https://img.shields.io/npm/v/harness-evolver?style=for-the-badge&color=blueviolet" alt="npm"></a> <a href="https://github.com/raphaelchristi/harness-evolver/blob/main/LICENSE"><img src="https://img.shields.io/badge/License-MIT-green?style=for-the-badge" alt="License: MIT"></a> <a href="https://arxiv.org/abs/2603.28052"><img src="https://img.shields.io/badge/Paper-Meta--Harness-FFD700?style=for-the-badge" alt="Paper"></a> <a href="https://github.com/raphaelchristi/harness-evolver"><img src="https://img.shields.io/badge/Built%20by-Raphael%20Valdetaro-ff69b4?style=for-the-badge" alt="Built by Raphael Valdetaro"></a> </p> Point at any LLM agent codebase. Harness Evolver will autonomously improve it — prompts, routing, tools, architecture — using multi-agent evolution with LangSmith as the evaluation backend. --- ## Install ### Claude Code Plugin (recommended)