Install

The most effort ponytail will ever ask of you:

The Claude Code and Codex plugins run two tiny Node.js lifecycle hooks, so node needs to be on your PATH (note for Nix/nvm users: it must be on the non-interactive shell's PATH). If it isn't, the skills still work, the always-on activation just stays quiet instead of erroring on every prompt.

Grok Build

grok plugin install DietrichGebert/ponytail --trust

Enable the plugin (off by default): /plugins → Plugins → Space on ponytail, or in ~/.grok/config.toml:

[plugins]
enabled = ["ponytail"]

Start a new session (or reload plugins). Skills show as /ponytail, /ponytail-review, /ponytail-audit, /ponytail-debt, /ponytail-gain, /ponytail-help. Verify with grok inspect. Grok can auto-invoke ponytail for coding tasks from its skill description; use /ponytail (or /ponytail lite, /ponytail full, /ponytail ultra) when activation needs to be explicit. Grok lifecycle hooks are not used because their SessionStart output cannot inject instructions.

AGENTS.md still works instruction-only from a checkout without the plugin.

That was it. He'd be proud. He won't say it.

Active every session, with a handful of commands (see Commands). /ponytail ultra exists for when the codebase has wronged you personally. Startup and mode-change text shows the current mode.

Set the level for every new session with the PONYTAIL_DEFAULT_MODE env var (lite/full/ultra/off), or a defaultMode field in ~/.config/ponytail/config.json (%APPDATA%\ponytail\config.json on Windows). The default is full.

While active, the ruleset is also injected into every subagent spawned via the Agent tool. To scope that to specific agent types (say, keep it off read-only search agents), set the PONYTAIL_SUBAGENT_MATCHER env var to a regex tested against the subagent's agent_type. It is unanchored and case-insensitive: explore|general matches either, ^general$ is exact, and plugin agent types look like plugin:name. Unset means inject into every subagent (the default); an invalid regex, or a subagent whose type the platform doesn't report, also falls back to injecting.

Cursor, Windsurf, Cline, GitHub Copilot Chat (the VS Code, JetBrains, and Visual Studio editor extension, not the standalone Copilot CLI covered under Install), Aider, Kiro, Zed, CodeWhale, Swival, Qoder: copy the matching rules file from this repo (.cursor/rules/, .windsurf/rules/, .clinerules/, .github/copilot-instructions.md, AGENTS.md, .kiro/steering/, .qoder/rules/).

Kiro: copy .kiro/steering/ponytail.md to ~/.kiro/steering/ (global) or .kiro/steering/ in your project.

GitHub Copilot CLI fallback (instruction-only mode): it reads AGENTS.md and .github/copilot-instructions.md in a project, or copy the rules into ~/.copilot/copilot-instructions.md to run ponytail in every project. This path keeps always-on guidance, but does not add plugin mode switches or hooks.

VS Code with the Codex extension reads AGENTS.md, which this repo ships, so it works from the repo root with no setup (~/.codex/AGENTS.md makes Codex global).

JetBrains Junie can read AGENTS.md once you point it there in Settings → Tools → Junie → Project Settings → Guidelines Path (it is not automatic yet). This repo ships AGENTS.md; .junie/guidelines.md is Junie's legacy path.

Amp (Sourcegraph) reads AGENTS.md from the working directory and parent directories up to $HOME, which this repo ships, so it works with no setup (~/.config/amp/AGENTS.md works globally).

Jules (Google) reads AGENTS.md from the repository root, which this repo ships, so it picks up the ruleset with no setup.

Which files map to which agent: Agent portability.

Uninstall

These remove the plugin's own files. They leave behind a small amount of state ponytail writes outside the plugin folder: the mode flag, ~/.config/ponytail/config.json, and (if you accepted the setup nudge) a statusLine entry in ~/.claude/settings.json. Run node scripts/uninstall.js to clean those up too. Run it before the host remove command above — the script is itself a plugin file, so removing the plugin first deletes it (or run it from a separate clone of this repo). It only removes the statusLine entry if it points at ponytail's own script, so a statusline you set up yourself is left untouched.

FAQ

Can I use it with caveman? Yes, and you should. Caveman shrinks what the agent says; ponytail shrinks what it builds. Different halves, no overlap: caveman leaves code byte-for-byte exact, ponytail stays out of the prose. Terse talk about minimal code.

Does it need a config file? No. An optional ~/.config/ponytail/config.json or PONYTAIL_DEFAULT_MODE env var can set the default level, but nothing is required.

What if I really need the 120-line cache class? You don't. Insist anyway and he'll build it. Slowly. Correctly. While looking at you.

Does it scale? The code you never wrote scales infinitely. Zero bugs, zero CVEs, 100% uptime since forever.

Why "ponytail"? You know exactly why.