A skill for Claude Code that gives engineering judgment when writing, refactoring, or testing code and building data-driven frontend UI. It activates on code review, legacy cleanup, tests, and complaints about bloat or over-engineering.
Claude Code
> /plugin marketplace add sayeed1999/agent-skills> /plugin install agent-skills@agent-skills
Codex
$ npx skills add sayeed1999/agent-skills -a codex
Cursor
$ npx skills add sayeed1999/agent-skills -a cursor
Gemini CLI
$ npx skills add sayeed1999/agent-skills -a gemini-cli
GitHub Copilot
$ copilot plugin marketplace add sayeed1999/agent-skills$ copilot plugin install agent-skills@agent-skills
OpenCode
$ npx skills add sayeed1999/agent-skills -a opencode
Windsurf
$ npx skills add sayeed1999/agent-skills -a windsurf
Instructions for your AI coding agent — not a library you import or an app you run.
This repo teaches your AI agent how to write and review code: ask before guessing, change only what was asked, prefer small, surgical fixes, and ship a working minimal version first.
Supported by Claude, Cursor, Codex, Gemini and other agent platforms.
This work was shaped by knowledge from earlier skill repositories such as andrej-karpathy-skills.
git clone https://github.com/sayeed1999/agent-skills.git
cd agent-skills
User-wide:
mkdir -p ~/.agents/skills
cp -r skills/battle-tested-engineer ~/.agents/skills/
Project-scoped:
mkdir -p .agents/skills
cp -r skills/battle-tested-engineer .agents/skills/
/battle-tested-engineer explain the codebase
That's it!
Ten principles for writing, reviewing, and refactoring code — plus a clear, concise output style for agent interactions (code, commits, and PR descriptions remain normal prose).
| Tool | Method | Recommended? |
|---|---|---|
| Any agent | Copy skills/battle-tested-engineer/ to ~/.agents/skills/ or .agents/skills/ | Yes (on-demand) |
| Cursor | Copy skills/battle-tested-engineer/ to ~/.cursor/skills/ | Yes (on-demand) |
| Cursor | Copy .cursor/rules/battle-tested-engineer.mdc to project .cursor/rules/ | Optional (always-on) |
| Claude Code | Plugin marketplace (see below) | Yes (global) |
| Claude Code | curl CLAUDE.md into project root | Per-project |
| Codex | Copy skill to ~/.codex/skills/ or .agents/skills/ | Yes (on-demand) |
| Codex | curl AGENTS.md into project root | Per-project |
.agents (any agent)User-wide:
mkdir -p ~/.agents/skills
cp -r skills/battle-tested-engineer ~/.agents/skills/
Project-scoped:
mkdir -p .agents/skills
cp -r skills/battle-tested-engineer .agents/skills/
From within Claude Code, add the marketplace:
/plugin marketplace add sayeed1999/agent-skills
Then install:
/plugin install agent-skills@agent-skills
New project:
curl -o CLAUDE.md https://raw.githubusercontent.com/sayeed1999/agent-skills/main/CLAUDE.md
Existing project (append):
echo "" >> CLAUDE.md
curl https://raw.githubusercontent.com/sayeed1999/agent-skills/main/CLAUDE.md >> CLAUDE.md
cp -r skills/battle-tested-engineer ~/.cursor/skills/
See CURSOR.md for always-apply rule setup and tradeoffs.
Global:
cp -r skills/battle-tested-engineer ~/.codex/skills/
Repo-scoped:
mkdir -p .agents/skills
cp -r skills/battle-tested-engineer .agents/skills/
See CODEX.md for AGENTS.md per-project install.
After install, you do not invoke the skill manually. Just open a project and talk to your agent as usual.
On-demand skill: loaded when the task fits (refactor, review, tests, UI). General questions may not trigger it.
Always-on rule or CLAUDE.md / AGENTS.md: guidelines apply every message in that project, including the concise output style during code work.
Optional: merge project-specific rules into the same files (see Customization).
These guidelines merge with project-specific instructions. Add sections like:
## Project-Specific Guidelines
- Use TypeScript strict mode
- All API endpoints must have tests
- Follow error handling in `src/utils/errors.ts`
These guidelines bias toward caution over speed. The skill applies a concise, no-friction output style for code work; it is opt-in when using on-demand installs or always-apply rules in tools like Cursor or per-project CLAUDE.md / AGENTS.md.
Use judgment for trivial tasks — not every edit requires full process.
agent-skills/
├── .claude-plugin/ # Claude Code plugin manifests
├── .cursor/rules/ # Optional always-apply Cursor rule
├── skills/ # Canonical skill definitions
│ └── battle-tested-engineer/
│ └── SKILL.md
├── CLAUDE.md # Claude Code per-project install
├── AGENTS.md # Codex per-project install
├── CURSOR.md # Cursor setup guide
├── CODEX.md # Codex setup guide
└── EXAMPLE.md # Good vs bad agent behavior
MIT
Stars on GitHub
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@facebookA skill for Claude Code that gives engineering judgment when writing, refactoring, or testing code and building data-driven frontend UI. It activates on code review, legacy cleanup, tests, and complaints about bloat or over-engineering. Install it with the command on its page. It includes battle-tested-engineer. Its skills do not fire on their own yet. Free and open source.
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