JWW Skills

Reusable agent skills for JWW projects. Each skill is a self-contained directory whose runtime instructions are in SKILL.md.

Installation

Xcode 27

Xcode 27 can install this repository as an Agent Plugins 1.0 plug-in. In Xcode → Settings → Intelligence → Plug-ins, choose Add Plug-in then Add from URL and enter the repository's Git URL. Select the individual skills to install after Xcode finishes cloning the plug-in.

The root plugin.json is the Xcode plug-in manifest. The existing skills/<name>/SKILL.md folders are the plug-in payload, so no MCP server or custom agent configuration is required. Xcode does not run Codex or Claude hooks and prompt wrappers: jww-handoff remains available for manual handoffs, while jww-codex-maintenance is intentionally unavailable because it requires Codex local-state and task-management capabilities.

Before creating a release, verify the intended release version against the manifest:

python3 scripts/validate-xcode-plugin.py --release-version 0.1.0

Skills CLI

Install a skill globally with the Skills CLI, replacing <skill-name> with its installed skill identifier. Repeat -a for each agent; a comma-separated list is rejected:

npx skills add justin/jww-skills \
  --skill <skill-name> \
  -a claude-code -a codex -a github-copilot \
  --global

jww-codex-maintenance is Codex-only. Install it separately with only the Codex target; its compatibility field documents the requirement but does not replace agent-specific installation:

npx skills add justin/jww-skills \
  --skill jww-codex-maintenance \
  -a codex \
  --global

Skills install to ~/.agents/skills/<skill-name>/ and are wired into each agent's own skills directory from there. The whole directory is preserved, so any prompts/ and hooks/ a skill ships arrive with it. Run npx skills add justin/jww-skills -a <agent> --list to see the agents the CLI supports, and npx skills update to refresh installed skills.

Install from a local checkout to test a skill before it is pushed:

npx skills add . --skill <skill-name> -a claude-code --global

Available skills are jww-bounded-investigation, jww-codex-maintenance, jww-git-workflow, jww-handoff, jww-repository-validation, and jww-swift-style.

npx skills add justin/jww-skills --list

For a manual installation, copy the desired skill directory into your agent harness's skills directory, preserving its internal structure:

cp -R skills/<directory-name> /path/to/your/skills/<skill-name>

Restart the agent session or reload installed skills after copying it. The SKILL.md file is required; agents/openai.yaml and assets/ provide Codex picker metadata and its icon.

Usage

Invoke an installed skill by name. In Claude Code, skills and slash commands are the same mechanism, so a skill is invocable directly:

/jww-swift-style

In Codex, reference the skill in a prompt:

Use $jww-swift-style to implement this Swift change.

An agent also loads a skill on its own when the request matches the skill's description, unless the skill's front matter restricts that.

Adding a Skill

Create a lowercase, hyphenated directory under skills/, such as skills/jww-swift-style/, with this structure:

skills/skill-name/
├── SKILL.md            # Instructions and YAML front matter
├── INSTALL.md          # Required when shipping prompts/ or hooks/
├── agents/openai.yaml  # Optional Codex picker metadata
├── prompts/<harness>/  # Optional per-harness invocation wrappers
├── hooks/              # Optional harness-specific automation scripts
└── assets/             # Referenced icons and other resources

Include name and description in SKILL.md front matter. State when the skill applies and when it does not. Keep instructions domain-specific, actionable, and tool-neutral unless a tool is required.

Validation

Review changed Markdown and YAML, confirm referenced assets exist, then run:

python3 scripts/validate-xcode-plugin.py
git diff --check

See AGENTS.md for contribution conventions.