Laconic

"He says nothing. He writes one line. It works."

Write less. Ship more. Laconic is a minimalism ruleset — a bundle of markdown skills that plug into your AI coding agent (Antigravity, VS Code Copilot, Claude Code, Codex, Cursor, Windsurf, Cline, and more) and teach it to walk a lazy-senior-dev ladder before writing a single line.

No API keys. No backend. No cost. Zero infrastructure. It's markdown that gets injected as system prompt into whatever agent you already use.

→ See it live · → Browse examples · → Contribute

The Ladder

Before writing any code, the agent stops at the first rung that holds:

1. Does this need to exist?     → no: skip it (YAGNI)
2. Already in this codebase?    → reuse it, don't rewrite
3. Stdlib does it?              → use it
4. Native platform feature?     → use it (<input type="date">, <dialog>, Intl, URL, fetch, pathlib, slices…)
5. Installed dependency?        → use it (no duplicate HTTP clients / date libs)
6. Open-source library exists?  → suggest it (real package name; never invent one)
7. One line?                    → one line
8. Only then:                    the minimum that works

The ladder runs after understanding the problem, never instead of it. Lazy about the solution — never about reading the code.

Before / after

You ask for a date picker. Your agent installs react-datepicker, writes a wrapper component, adds three stylesheets, and starts a discussion about timezones.

With Laconic:

<!-- laconic: browser has one -->
<input type="date" />

→ 8 more real-world examples — Python retry, JS deep-clone, Go slice utils, form validation, event emitter, lodash alternatives, Node file helpers.

Install — VS Code (Copilot Chat)

Copy Laconic's instructions into your project (or globally):

# in your project root
mkdir -p .github
curl -o .github/copilot-instructions.md \
  https://raw.githubusercontent.com/SDM002/Universal-Code/main/.github/copilot-instructions.md

# also drop AGENTS.md — most modern agents read this
curl -o AGENTS.md \
  https://raw.githubusercontent.com/SDM002/Universal-Code/main/AGENTS.md

Reload the VS Code window (or restart Copilot Chat). Your agent now walks the ladder on every prompt. To make it global, drop the same files at ~/.copilot/copilot-instructions.md.

Install — Google Antigravity

Antigravity CLI (the agy binary) installs Laconic like any Gemini extension:

agy plugin install https://github.com/SDM002/Universal-Code

That's it. The AGENTS.md and the five skill commands (/laconic, /laconic-review, /laconic-explain, /laconic-libs, /laconic-minimal) become available in every session.

For the Antigravity IDE / agent workspace, drop AGENTS.md at the workspace root — Antigravity auto-loads it as always-on context.

Install — Other agents (bonus)

Laconic is just markdown. Copy the matching file into any agent that reads it:

| Agent | Where | | --- | --- | | VS Code Copilot Chat | .github/copilot-instructions.md (project) or ~/.copilot/copilot-instructions.md (global) | | Antigravity / Gemini CLI | agy plugin install <repo> or drop AGENTS.md in workspace | | Claude Code | AGENTS.md at repo root | | Codex CLI | AGENTS.md at repo root (or ~/.codex/AGENTS.md globally) | | Cursor | .cursor/rules/laconic.md | | Windsurf | .windsurf/rules/laconic.md | | Cline | .clinerules/laconic.md | | JetBrains Junie | Settings → Junie → Guidelines Path → point at AGENTS.md | | Amp / Jules / CodeWhale | AGENTS.md at repo root (auto-loaded) |

Commands

Available in skill-capable agents (Antigravity, Claude Code, Codex, OpenCode, and any host that supports /skills).

| Command | What it does | | --- | --- | | /laconic | Show the ladder and current mode. | | /laconic-review | Review the current diff for over-engineering. Returns a delete-list. | | /laconic-explain | Line-by-line what / why / how for the current file or selection. | | /laconic-libs | Suggest existing open-source libraries that would replace the code. Real packages only. | | /laconic-minimal | Rewrite the current code as the minimum that works. Preserves behavior, security, and accessibility. | | /laconic-tests | Write the smallest test that would have caught the bug. No new test-framework deps. | | /laconic-security | Trust-boundary audit of the current diff. Ranked by exploitability, not CVSS theatre. |

In VS Code Copilot Chat (no /skills support), just paste the intent into chat: "review this diff with laconic", "explain this function laconic-style", "suggest a library instead of this hand-rolled code".

Language cheat sheets

Per-language memory banks so the agent stops reinventing stdlib:

• Python — skills/lang/python.md
• JavaScript / Node — skills/lang/js.md
• TypeScript — skills/lang/typescript.md
• Go — skills/lang/go.md
• Rust — skills/lang/rust.md

Want another language? Open an issue or send a PR.

Extra skills

• skills/laconic-tests.md — write the smallest test that would have caught the bug.
• skills/laconic-security.md — trust-boundary audit; no CVSS theatre.

Benchmark

How lazy is laconic? Run the harness:

node bench/run.mjs

Current numbers across the examples in this repo:

TOTAL       before: 143 lines      after: 46 lines      saved: 97 lines (68%)

The harness reads every ## Before / ## After block under examples/. Add an example — the bench picks it up automatically. See bench/README.md.

Non-negotiables

Laziness stops at these lines. Laconic will never cut:

• Trust-boundary validation (user → server, disk → memory, network deserialization).
• Security (auth, secrets, SQL/NoSQL injection, XSS, CSRF, path traversal).
• Data-loss handling (transactions, atomic writes, idempotency keys).
• Accessibility (semantic HTML, keyboard focus, alt, label, ARIA).
• Error handling at real failure modes (network, disk, races).

The code you never wrote has zero bugs, zero CVEs, zero maintenance, and 100% uptime. The code that guards your users' data stays.

Repo layout

Universal-Code/
├── skills/                 the ruleset — this is what plugs into agents
│   ├── laconic.md          the main always-on ladder
│   ├── laconic-*.md        skill commands (review, explain, libs, minimal, tests, security)
│   └── lang/               per-language stdlib cheat sheets (py, js, ts, go, rust)
├── examples/               before / after gallery (start here if you're new)
├── bench/                  zero-dep harness — measures reduction across examples
├── AGENTS.md               universal file most agents auto-load
├── gemini-extension.json   Antigravity / Gemini CLI plugin manifest
├── .github/
│   ├── copilot-instructions.md   VS Code Copilot Chat
│   ├── ISSUE_TEMPLATE/           bug / new agent / new language
│   ├── PULL_REQUEST_TEMPLATE.md
│   └── workflows/lint.yml        markdown lint on PR
├── frontend/               React landing page (deployed live)
├── backend/                minimal FastAPI health-check
├── package.json
├── LICENSE                 MIT
├── README.md               this file
├── CONTRIBUTING.md
└── SECURITY.md

Contributing

Laconic is markdown. Contributing means adding or sharpening a rule — no code required. See CONTRIBUTING.md. The single highest-leverage contribution is a failing prompt: "I asked Copilot X with laconic loaded, and it still over-built."

FAQ

Does it need an API key? No. Laconic is markdown. Your existing agent's model does the work.

What about the 120-line cache class I actually need? Ask for it. Laconic will build it, correctly, while making a note of it.

Does it work with GPT-5.4 / Claude Opus 4.8 / Gemini 3 Pro? Yes. It's agent-agnostic — plug it into whatever agent shells around whatever model you use.

Why "Laconic"? Laconic (adj.): using few words. From Sparta. They had a reputation.

License

MIT. The shortest license that works.