chore: vendor Ponytail as repository-local Codex plugin

.agents/plugins/marketplace.json

@@ -0,0 +1,19 @@
+{
+  "name": "llama-cpp-local",
+  "interface": {
+    "displayName": "llama.cpp local plugins"
+  },
+  "plugins": [
+    {
+      "name": "ponytail",
+      "source": {
+        "source": "local",
+        "path": "./third_party/ponytail"
+      },
+      "category": "Productivity",
+      "policy": {
+        "installation": "AVAILABLE"
+      }
+    }
+  ]
+}

.agents/skills/README.md

@@ -52,3 +52,9 @@ The lock file generated by the updater becomes the ongoing record of installed c
 ## Repository setup
 
 After installing or materially updating the bundle, run `/setup-matt-pocock-skills` when repository-specific tracker, triage-label, or documentation configuration needs to be initialized or refreshed.
+
+## Ponytail
+
+Ponytail is **not** part of this vendored skill directory. It is installed as the official Codex plugin because its standard behavior depends on lifecycle hooks and runtime mode state, not only its six skills. See [docs/agents/ponytail.md](../../docs/agents/ponytail.md).
+
+Do not add Ponytail skill names to the Matt Pocock update allowlist; that would create duplicate skill installations.

docs/agents/ponytail.md

@@ -0,0 +1,118 @@
+# Ponytail integration
+
+This repository carries a reviewable copy of the **official Ponytail Codex plugin**
+from [DietrichGebert/ponytail](https://github.com/DietrichGebert/ponytail).
+
+The canonical project copy lives at:
+
+`third_party/ponytail/`
+
+Codex sees it through the repository marketplace:
+
+`.agents/plugins/marketplace.json`
+
+This keeps Ponytail's standard architecture intact while making the exact hooks and
+skills used by this project part of the repository history.
+
+## What is vendored
+
+The project copy includes Ponytail's Codex runtime payload:
+
+- native `.codex-plugin/plugin.json`
+- lifecycle hooks
+- all six Ponytail skills
+- package metadata
+- upstream `AGENTS.md`
+- MIT license
+- uninstall helper
+- upstream logo asset
+
+The executable hook and skill files are copied from upstream unchanged.
+
+There is one packaging-only difference: the local manifest points its cosmetic icon
+fields at Ponytail's upstream `assets/logo-dark.svg` instead of the much larger PNG.
+This does not change Ponytail behavior.
+
+The exact upstream commit is recorded in:
+
+`third_party/ponytail/UPSTREAM_REVISION`
+
+## Install
+
+Windows:
+
+```powershell
+./scripts/setup-ponytail.ps1
+```
+
+POSIX:
+
+```bash
+./scripts/setup-ponytail.sh
+```
+
+The setup registers this repository as a local Codex marketplace when needed and
+installs:
+
+`ponytail@llama-cpp-local`
+
+Codex supports repository marketplaces at `.agents/plugins/marketplace.json` and
+local plugin entries that point at another path in the same repository.
+
+## Hook trust
+
+After installation, start Codex and open:
+
+`/hooks`
+
+Review and trust Ponytail's hooks. Do not bypass this approval boundary.
+
+The standard plugin then provides:
+
+- `SessionStart`: activates Ponytail and injects the active ruleset.
+- `UserPromptSubmit`: tracks `lite`, `full`, `ultra`, and `off` mode changes.
+- `SubagentStart`: propagates the active ruleset to subagents.
+
+Node.js must be available on `PATH`.
+
+## Default mode
+
+Ponytail's upstream default remains **full**. This repository does not override it.
+
+## Updating
+
+Refresh the project copy from upstream with:
+
+Windows:
+
+```powershell
+./scripts/update-ponytail.ps1
+```
+
+POSIX:
+
+```bash
+./scripts/update-ponytail.sh
+```
+
+The updater shallow-clones current upstream `main`, replaces only the vendored
+Ponytail runtime payload, records the new upstream commit, and reapplies the single
+cosmetic SVG icon-path adaptation.
+
+Always inspect the resulting hook and skill diff before committing. Ponytail updates
+can change executable lifecycle code, not just prompts.
+
+After accepting an update, restart Codex/ChatGPT so the local plugin cache refreshes
+from the updated repository source.
+
+## Relationship to Matt Pocock skills
+
+The systems intentionally remain separate:
+
+- Matt Pocock skills: project-local skill copies under `.agents/skills/`, managed by
+  the `skills` CLI and `skills-lock.json`.
+- Ponytail: a complete local Codex plugin under `third_party/ponytail/`, exposed
+  through the repository marketplace.
+
+Do not separately install Ponytail's six skills with the `skills` CLI; the plugin is
+their authoritative source and also supplies their lifecycle behavior.

scripts/setup-ponytail.ps1

@@ -0,0 +1,37 @@
+$ErrorActionPreference = "Stop"
+
+function Require-Command([string]$Name) {
+    if (-not (Get-Command $Name -ErrorAction SilentlyContinue)) {
+        throw "'$Name' is required but was not found on PATH."
+    }
+}
+
+Require-Command "node"
+Require-Command "codex"
+
+$RepoRoot = Split-Path -Parent $PSScriptRoot
+Push-Location $RepoRoot
+try {
+    $marketplaces = (& codex plugin marketplace list 2>&1 | Out-String)
+    if ($marketplaces -notmatch "llama-cpp-local") {
+        Write-Host "Registering the repository-local plugin marketplace..."
+        & codex plugin marketplace add .
+        if ($LASTEXITCODE -ne 0) {
+            throw "Failed to register the repository-local marketplace."
+        }
+    }
+
+    Write-Host "Installing Ponytail from the repository-local marketplace..."
+    & codex plugin add ponytail@llama-cpp-local
+    if ($LASTEXITCODE -ne 0) {
+        throw "Failed to install the local Ponytail plugin."
+    }
+}
+finally {
+    Pop-Location
+}
+
+Write-Host ""
+Write-Host "Ponytail is installed from third_party/ponytail."
+Write-Host "Start Codex, open /hooks, review Ponytail's hooks, and trust them."
+Write-Host "Ponytail's upstream default mode is full."

scripts/setup-ponytail.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+command -v node >/dev/null 2>&1 || { echo "node is required but was not found on PATH." >&2; exit 1; }
+command -v codex >/dev/null 2>&1 || { echo "codex is required but was not found on PATH." >&2; exit 1; }
+
+repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+cd "$repo_root"
+
+if ! codex plugin marketplace list 2>&1 | grep -q 'llama-cpp-local'; then
+  echo "Registering the repository-local plugin marketplace..."
+  codex plugin marketplace add .
+fi
+
+echo "Installing Ponytail from the repository-local marketplace..."
+codex plugin add ponytail@llama-cpp-local
+
+cat <<'EOF'
+
+Ponytail is installed from third_party/ponytail.
+Start Codex, open /hooks, review Ponytail's hooks, and trust them.
+Ponytail's upstream default mode is full.
+EOF

scripts/update-ponytail.ps1

@@ -0,0 +1,83 @@
+$ErrorActionPreference = "Stop"
+
+function Require-Command([string]$Name) {
+    if (-not (Get-Command $Name -ErrorAction SilentlyContinue)) {
+        throw "'$Name' is required but was not found on PATH."
+    }
+}
+
+Require-Command "git"
+
+$RepoRoot = Split-Path -Parent $PSScriptRoot
+$Dest = Join-Path $RepoRoot "third_party/ponytail"
+$Temp = Join-Path ([System.IO.Path]::GetTempPath()) ("ponytail-" + [guid]::NewGuid().ToString("N"))
+
+try {
+    & git clone --depth 1 https://github.com/DietrichGebert/ponytail.git $Temp
+    if ($LASTEXITCODE -ne 0) {
+        throw "Failed to clone DietrichGebert/ponytail."
+    }
+
+    $Revision = (& git -C $Temp rev-parse HEAD).Trim()
+
+    if (Test-Path $Dest) {
+        Remove-Item -Recurse -Force $Dest
+    }
+    New-Item -ItemType Directory -Force -Path $Dest | Out-Null
+    New-Item -ItemType Directory -Force -Path (Join-Path $Dest "assets") | Out-Null
+    New-Item -ItemType Directory -Force -Path (Join-Path $Dest "scripts") | Out-Null
+
+    Copy-Item -Recurse (Join-Path $Temp ".codex-plugin") $Dest
+    Copy-Item -Recurse (Join-Path $Temp "hooks") $Dest
+    Copy-Item -Recurse (Join-Path $Temp "skills") $Dest
+    Copy-Item (Join-Path $Temp "AGENTS.md") $Dest
+    Copy-Item (Join-Path $Temp "LICENSE") $Dest
+    Copy-Item (Join-Path $Temp "package.json") $Dest
+    Copy-Item (Join-Path $Temp "scripts/uninstall.js") (Join-Path $Dest "scripts/uninstall.js")
+    Copy-Item (Join-Path $Temp "assets/logo-dark.svg") (Join-Path $Dest "assets/logo-dark.svg")
+
+    $ManifestPath = Join-Path $Dest ".codex-plugin/plugin.json"
+    $Manifest = [System.IO.File]::ReadAllText($ManifestPath)
+    $Manifest = $Manifest.Replace("./assets/logo.png", "./assets/logo-dark.svg")
+    [System.IO.File]::WriteAllText($ManifestPath, $Manifest, [System.Text.UTF8Encoding]::new($false))
+
+    [System.IO.File]::WriteAllText(
+        (Join-Path $Dest "UPSTREAM_REVISION"),
+        $Revision + [Environment]::NewLine,
+        [System.Text.UTF8Encoding]::new($false)
+    )
+
+    $VendorNote = @"
+# Vendored Ponytail plugin
+
+Source: https://github.com/DietrichGebert/ponytail
+
+Upstream revision: `$Revision`
+
+This directory contains Ponytail's Codex runtime payload: its native plugin manifest,
+lifecycle hooks, six skills, package metadata, license, upstream AGENTS.md, uninstall
+helper, and logo asset.
+
+The runtime files are copied from upstream unchanged except for one packaging-only
+manifest adjustment: the icon paths use the upstream `assets/logo-dark.svg` instead
+of `assets/logo.png`. This avoids carrying a large binary asset while leaving all
+skills and executable hook behavior unchanged.
+
+Refresh with `scripts/update-ponytail.ps1` or `scripts/update-ponytail.sh`, then
+review the full diff before committing.
+"@
+    [System.IO.File]::WriteAllText(
+        (Join-Path $Dest "VENDORED.md"),
+        $VendorNote,
+        [System.Text.UTF8Encoding]::new($false)
+    )
+
+    Write-Host "Ponytail vendored at upstream revision $Revision"
+    Write-Host "Review: git diff -- third_party/ponytail"
+    Write-Host "Restart Codex/ChatGPT after accepting the update so the local plugin cache refreshes."
+}
+finally {
+    if (Test-Path $Temp) {
+        Remove-Item -Recurse -Force $Temp
+    }
+}

scripts/update-ponytail.sh

@@ -0,0 +1,62 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+command -v git >/dev/null 2>&1 || { echo "git is required but was not found on PATH." >&2; exit 1; }
+
+repo_root="$(cd "$(dirname "$0")/.." && pwd)"
+dest="$repo_root/third_party/ponytail"
+tmp="$(mktemp -d)"
+
+cleanup() {
+  rm -rf "$tmp"
+}
+trap cleanup EXIT
+
+git clone --depth 1 https://github.com/DietrichGebert/ponytail.git "$tmp/src"
+revision="$(git -C "$tmp/src" rev-parse HEAD)"
+
+rm -rf "$dest"
+mkdir -p "$dest/assets" "$dest/scripts"
+
+cp -R "$tmp/src/.codex-plugin" "$dest/"
+cp -R "$tmp/src/hooks" "$dest/"
+cp -R "$tmp/src/skills" "$dest/"
+cp "$tmp/src/AGENTS.md" "$dest/"
+cp "$tmp/src/LICENSE" "$dest/"
+cp "$tmp/src/package.json" "$dest/"
+cp "$tmp/src/scripts/uninstall.js" "$dest/scripts/"
+cp "$tmp/src/assets/logo-dark.svg" "$dest/assets/"
+
+python3 - "$dest/.codex-plugin/plugin.json" <<'PY'
+from pathlib import Path
+import sys
+p = Path(sys.argv[1])
+s = p.read_text(encoding="utf-8")
+p.write_text(s.replace("./assets/logo.png", "./assets/logo-dark.svg"), encoding="utf-8")
+PY
+
+printf '%s\n' "$revision" > "$dest/UPSTREAM_REVISION"
+
+cat > "$dest/VENDORED.md" <<EOF
+# Vendored Ponytail plugin
+
+Source: https://github.com/DietrichGebert/ponytail
+
+Upstream revision: `$revision`
+
+This directory contains Ponytail's Codex runtime payload: its native plugin manifest,
+lifecycle hooks, six skills, package metadata, license, upstream AGENTS.md, uninstall
+helper, and logo asset.
+
+The runtime files are copied from upstream unchanged except for one packaging-only
+manifest adjustment: the icon paths use the upstream `assets/logo-dark.svg` instead
+of `assets/logo.png`. This avoids carrying a large binary asset while leaving all
+skills and executable hook behavior unchanged.
+
+Refresh with `scripts/update-ponytail.ps1` or `scripts/update-ponytail.sh`, then
+review the full diff before committing.
+EOF
+
+echo "Ponytail vendored at upstream revision $revision"
+echo "Review: git diff -- third_party/ponytail"
+echo "Restart Codex/ChatGPT after accepting the update so the local plugin cache refreshes."

third_party/ponytail/.codex-plugin/plugin.json

@@ -0,0 +1,32 @@
+{
+  "name": "ponytail",
+  "version": "4.10.0",
+  "description": "Lazy senior dev mode. Forces the simplest, shortest solution that actually works: YAGNI, stdlib first, no unrequested abstractions.",
+  "author": {
+    "name": "Dietrich Gebert",
+    "url": "https://github.com/DietrichGebert"
+  },
+  "homepage": "https://github.com/DietrichGebert/ponytail",
+  "repository": "https://github.com/DietrichGebert/ponytail",
+  "license": "MIT",
+  "keywords": ["yagni", "minimalism", "code-review", "productivity"],
+  "skills": "./skills/",
+  "hooks": "./hooks/claude-codex-hooks.json",
+  "interface": {
+    "displayName": "Ponytail",
+    "shortDescription": "Lazy senior developer mode",
+    "longDescription": "Prefer YAGNI, the standard library, native platform features, and the smallest correct implementation.",
+    "developerName": "Dietrich Gebert",
+    "category": "Productivity",
+    "capabilities": ["Instructions", "Lifecycle hooks"],
+    "websiteURL": "https://github.com/DietrichGebert/ponytail",
+    "defaultPrompt": [
+      "Use Ponytail mode for this task.",
+      "Review this diff for over-engineering.",
+      "Find the smallest correct implementation."
+    ],
+    "brandColor": "#111111",
+    "composerIcon": "./assets/logo-dark.svg",
+    "logo": "./assets/logo-dark.svg"
+  }
+}