Claude Code plugin

Better Harness

An open-source Harness Engineering platform for coding agents—define harnesses as code, run controlled experiments, inspect evidence, and compare outcomes. Turn task evidence into actionable team and organization insights.

2,435 stars 204 forksPlugins & marketplaces Plugin marketplace Source

Install

Inside Claude Code
/plugin marketplace add QoderAI/better-harness

Found in the project README. Check it for setup steps after installing.

From source
git clone https://github.com/QoderAI/better-harness.git

From the README

Better Harness

  English · 简体中文

  Delegate coding to agents. Improve the loop around them.

  Better Harness provides open-source insights for the Agent Work Loop. It runs
  through your Coding Agent and turns project and session evidence into prioritized
  improvements and verifiable next steps. Missing evidence stays explicit.

  Website ·
  Choose your host ·
  Sample report ·
  Docs

Quick start

Analyze and improve your coding workflow with: Claude Code, Codex Desktop, Codex CLI, Qoder Desktop/CLI, Cursor, or GitHub Copilot CLI.

Choose the host you already use to get its exact installation, verification,
invocation, and report-output steps. Better Harness does not use one universal
entrypoint across every host.

This README shows inline setup for the most common hosts. Additional supported
hosts (Qwen Code, Pi, Kimi Code, WorkBuddy, and Grok) keep their steps and
boundaries in the installation guide and the
public Host Adapter Matrix; see
More adapters. README placement is a display choice, not a
support-level claim.

Better Harness scopes behavior claims to relevant Task Episodes and the
surrounding project mechanisms. Qoder and Cursor produce host-native Canvas
reports; Claude Code, Codex, Qwen Code, GitHub Copilot, and Kimi Code produce
self-contained HTML with paired Markdown. Missing or partial evidence remains
explicit. See the Host Adapter Matrix for current
coverage and output differences.

See it in action

The report keeps missing evidence explicit and turns supported gaps into
prioritized findings with an impact, expected output, scoped repair, and
acceptance checks.

  Open the complete self-contained English HTML report
  (source).

For delivery tracing, the interactive Harness Inspector
follows product intent through agent activity, sessions,…
Read the full README on GitHub

How plugins work

  • A plugin bundles slash commands, subagents, skills, hooks, MCP servers and status lines so they install together.
  • Add the marketplace inside Claude Code with /plugin marketplace add QoderAI/better-harness, then run /plugin to pick what to install.
  • You can turn a plugin off again from /plugin without deleting anything.
Claude Code docs

Details

Language
JavaScript
License
MIT
Last updated
20 October 2026
Topics
agent-pluginclaude-codecodexcursorharness-designharness-engineeringloop-engineeringqoderskill

FAQ

What is Better Harness?

An open-source Harness Engineering platform for coding agents—define harnesses as code, run controlled experiments, inspect evidence, and compare outcomes. Turn task evidence into actionable team and organization insights. It is a plugin for Claude Code, from QoderAI/better-harness on GitHub.

How do I install Better Harness?

Run /plugin marketplace add QoderAI/better-harness inside Claude Code, then follow the setup in the README.

Is Better Harness popular?

QoderAI/better-harness has 2,435 GitHub stars and 204 forks, and is included in 1 curated Claude Code list. It was last updated on 20 October 2026.

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