Upgrade Harness

Upgrade Harness is an Automation skill for Claude Code, published by ruvnet in metaharness.

609 stars72 forkson ruvnet/metaharnessAdded 2026/08/25+2% in starsRepository updated 2026/08/24

agent-harnessagent-harness-generatoragent-scaffoldingagentic-aiagentic-frameworkautonomous-agentsclaude-codecodexcreate-agent-harnesshermes-agentmcpmcp-servermulti-agentopenai-codexopenclawpi-devrvmsandboxingscaffoldscaffolding

Install in seconds

Install Upgrade Harness

Copy Upgrade Harness into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/ruvnet/metaharness/tree/main/.claude-plugin/skills/upgrade-harness ~/.claude/skills/upgrade-harness

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/ruvnet/metaharness.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: .claude-plugin/skills/upgrade-harness/SKILL.md in ruvnet/metaharness
Installs to: ~/.claude/skills/upgrade-harness
Collection: One of 16 skills cataloged from this repository
Category: Automation — 1523 skills

What Upgrade Harness does

Upgrade Harness re-renders a scaffolded harness against the latest template, compares added, removed, and changed files, and applies safe updates. Use it to catch template drift and resolve conflicts with markers or .rej files.

Upgrade Harness is cataloged under Automation on DirSkills. Upgrade Harness comes from a repository tagged agent-harness, agent-harness-generator, agent-scaffolding, agentic-ai and agentic-framework.

Documentation

README

Excerpt

upgrade-harness

Codex skill: drift detection + apply for a scaffolded harness.

What it does

Re-renders the template that produced the harness against the current generator version, using the same vars the original scaffold used. Computes a 3-bucket plan:

Bucket	Meaning
added	upstream template now has files the harness doesn't
removed	upstream template no longer has files the harness does
changed	upstream and harness differ; sub-classified `clean` vs `conflict`

A clean change means the harness's version equals the original generation — apply safely. A conflict means the user edited the file post-scaffold; the apply step writes either Git-style inline markers or a .rej sidecar for manual merge.

Usage from Codex

This is the opening of the README. Read the full README on GitHub.

Commands Upgrade Harness provides

Slash commands named in this skill’s SKILL.md, listed in the order they first appear.

/upgrade-harness

Frequently asked about Upgrade Harness

What else does ruvnet publish alongside Upgrade Harness?
Upgrade Harness is one of 16 skills that DirSkills catalogs from ruvnet/metaharness, the repository it ships in. Its siblings there include Compare Harnesses, Create Harness and Darwin Mode. Each one is a separate skill with its own page in this directory, installs the same way Upgrade Harness does, and is maintained by ruvnet in that same repository. The rest of the collection is listed on the ruvnet/metaharness page.
How does Upgrade Harness compare to other Automation skills?
Upgrade Harness ranks #1183 by stars among the 1523 Automation skills in this catalog. The most-starred ones next to it are Autonomous Loops, Autonomous Agent Harness and Automation Audit Ops. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Upgrade Harness against them. Open each page to compare what they document and how they install.