harness-sync

Sync your curated AI coding skills across projects and coding agents.

About

Stop losing track of which skills are applied to which project for which coding agent. Stop manually copying the same skills into different projects.

harness-sync lets you maintain a single private catalog of skills on GitHub and apply them to any project with one command. It supports OpenCode, Claude Code, and Codex CLI.

Features

• One catalog, many projects - Keep your curated skills in a single GitHub repo
• Multi-agent support - Apply skills to OpenCode, Claude Code, and Codex CLI simultaneously
• Applied status tracking - See which skills are already in your current project
• Interactive or scripted - Use the TUI or automate with flags

Installation

npm i -g harness-sync
# or
pnpm add -g harness-sync
# or
bun add -g harness-sync

Verify:

harness-sync --version

Requirements

• GitHub CLI (gh) installed and authenticated
• Access to your catalog repo

Quick Start

# 1. Point to your catalog repo
harness-sync init

# 2. See available skills
harness-sync list

# 3. Apply skills interactively
harness-sync apply

Running harness-sync with no arguments launches the interactive apply flow.

Commands

| Command | Description | |---------|-------------| | harness-sync init | Configure your catalog repo (owner/repo format) | | harness-sync list | List skills with applied status | | harness-sync apply | Interactively select and apply skills | | harness-sync | Alias for apply |

Non-interactive apply

For CI or scripting:

harness-sync apply --skills alpha,beta --harnesses opencode,claude,codex --yes

| Flag | Description | |------|-------------| | --skills <ids> | Comma-separated skill IDs | | --harnesses <targets> | opencode, claude, and/or codex | | --yes, -y | Skip confirmation prompts |

Setting Up Your Catalog

Your catalog repo needs a skills/ directory. Each skill is a folder containing a SKILL.md with YAML frontmatter:

my-catalog/
└── skills/
    ├── code-review/
    │   ├── SKILL.md
    │   └── prompts/
    └── testing/
        └── SKILL.md

SKILL.md format:

---
name: Code Review
description: Guidelines for thorough code reviews
---

[Skill content here]

Where Skills Go

Skills are copied to harness-specific folders in your project root:

| Harness | Destination | |---------|-------------| | OpenCode | .opencode/skills/<skill-id>/ | | Claude Code | .claude/skills/<skill-id>/ | | Codex CLI | .codex/skills/<skill-id>/ |

Existing skills prompt for confirmation before overwriting (unless --yes is used).

Configuration

The catalog repo setting is stored at:

~/.config/harness-sync/config.json

Or $XDG_CONFIG_HOME/harness-sync/config.json if XDG_CONFIG_HOME is set.

License

MIT