Add standalone Codex skill installation

.github/checks.py

@@ -48,7 +48,7 @@ def ok(msg):
 except Exception as e:
     fail(f"version check: {e}")
 
-# 3. All four skills exist with frontmatter name + description
+# 3. All four skills exist with frontmatter name + description and Codex metadata
 for skill in ["fable-method", "fable-loop", "fable-judge", "fable-domain"]:
     path = os.path.join(ROOT, "skills", skill, "SKILL.md")
     try:
@@ -61,6 +61,19 @@ def ok(msg):
     except Exception as e:
         fail(f"skills/{skill}/SKILL.md: {e}")
 
+    metadata_path = os.path.join(ROOT, "skills", skill, "agents", "openai.yaml")
+    try:
+        with io.open(metadata_path, encoding="utf-8") as f:
+            metadata = f.read()
+        required = ["interface:", "display_name:", "short_description:", "default_prompt:"]
+        missing = [field for field in required if field not in metadata]
+        if missing or f"${skill}" not in metadata:
+            fail(f"skills/{skill}/agents/openai.yaml: missing fields or skill prompt")
+        else:
+            ok(f"skills/{skill}/agents/openai.yaml valid")
+    except Exception as e:
+        fail(f"skills/{skill}/agents/openai.yaml: {e}")
+
 # 4. Domain adapters all carry a binding minimum evidence set and a fraud table
 domains_dir = os.path.join(ROOT, "skills", "fable-method", "references", "domains")
 for name in sorted(os.listdir(domains_dir)):

.github/workflows/checks.yml

@@ -13,3 +13,24 @@ jobs:
           python-version: "3.12"
       - name: Validate manifests, skills, adapters, evidence, and style
         run: python .github/checks.py
+      - name: Smoke-test Bash installers
+        run: |
+          claude_home="$(mktemp -d)"
+          bash install.sh --claude --dest "$claude_home/skills"
+          test -f "$claude_home/skills/fable-domain/SKILL.md"
+          codex_home="$(mktemp -d)"
+          CODEX_HOME="$codex_home" bash install.sh --codex
+          test -f "$codex_home/skills/fable-domain/SKILL.md"
+          test -f "$codex_home/skills/fable-method/agents/openai.yaml"
+      - name: Smoke-test PowerShell Codex installer
+        shell: pwsh
+        run: |
+          $claudeSkills = Join-Path $env:RUNNER_TEMP "fable-claude-skills"
+          $codexSkills = Join-Path $env:RUNNER_TEMP "fable-codex-skills"
+          ./install.ps1 -Target claude -Destination $claudeSkills
+          ./install.ps1 -Target codex -Destination $codexSkills
+          foreach ($destination in @($claudeSkills, $codexSkills)) {
+            if (-not (Test-Path (Join-Path $destination "fable-domain/SKILL.md"))) {
+              throw "fable-domain was not installed into $destination"
+            }
+          }

README.md

@@ -80,15 +80,27 @@ Seven more charts (ask classification with tie-breaks, the bounded evidence loop
 
 All four skills arrive namespaced (`/fable:fable-method`, `/fable:fable-loop`, `/fable:fable-judge`, `/fable:fable-domain`), versioned, and updatable via `/plugin marketplace update`.
 
-**As standalone skills** (un-namespaced `/fable-method` etc.):
+**As standalone Claude Code skills** (un-namespaced `/fable-method` etc.):
 
 ```bash
-git clone https://github.com/Sahir619/fable-method && bash fable-method/install.sh
+git clone https://github.com/Sahir619/fable-method && bash fable-method/install.sh --claude
 ```
 
-Windows PowerShell: `git clone https://github.com/Sahir619/fable-method; .\fable-method\install.ps1`
+Windows PowerShell: `git clone https://github.com/Sahir619/fable-method; .\fable-method\install.ps1 -Target claude`
 
-**Any other agent** (Codex, Cursor, aider, a raw system prompt): use [AGENTS.md](AGENTS.md), the identical method without Claude-specific frontmatter.
+**As Codex skills:**
+
+```bash
+git clone https://github.com/Sahir619/fable-method && bash fable-method/install.sh --codex
+```
+
+Windows PowerShell: `git clone https://github.com/Sahir619/fable-method; .\fable-method\install.ps1 -Target codex`
+
+All four skills are installed into `$CODEX_HOME/skills`, or `~/.codex/skills` when `CODEX_HOME` is unset. They are available to Codex in a new turn.
+
+Both installers accept a custom destination for isolated or project-specific installs: `--dest PATH` in Bash or `-Destination PATH` in PowerShell.
+
+**Any other agent** (Cursor, aider, a raw system prompt): use [AGENTS.md](AGENTS.md), the identical method without product-specific frontmatter.
 
 **Make it proactive (recommended).** Skills fire best when nobody has to remember them. Add to your global `~/.claude/CLAUDE.md`:
 
@@ -166,9 +178,10 @@ skills/
   fable-loop/               the orchestrated plan-execute-verify-audit workflow
   fable-judge/              adversarial verification of finished work + trap suite
   fable-domain/             generates new domain adapter bundles (adapter + trap + smoke eval)
+  */agents/openai.yaml      optional Codex display metadata for each skill
 AGENTS.md                   the same method for any other harness
 DOC.md                      plain-language explainer: the flow, what changed since 1.3, why it is better
-install.sh / install.ps1    standalone-skill install into ~/.claude/skills/ (plugin preferred)
+install.sh / install.ps1    standalone install into Claude Code or Codex skill directories
 eval/
   README.md                 methodology + how to reproduce
   RESULTS.md                dated round-by-round results log (wins, nulls, and failures)

install.ps1

@@ -1,15 +1,31 @@
-# Manual installer (Windows PowerShell) for users who prefer standalone
-# skills over the plugin. Plugin install (recommended): inside Claude Code run
-#   /plugin marketplace add Sahir619/fable-method
-#   /plugin install fable@fable-method
+param(
+    [ValidateSet("claude", "codex")]
+    [string]$Target = "claude",
+    [string]$Destination
+)
+
+# Standalone skill installer for Windows PowerShell.
+# Usage: .\install.ps1 [-Target claude|codex] [-Destination PATH]
 $ErrorActionPreference = "Stop"
 $src = $PSScriptRoot
-$dst = Join-Path $HOME ".claude\skills"
+
+if ($Destination) {
+    $dst = $Destination
+    $product = if ($Target -eq "codex") { "Codex" } else { "Claude Code" }
+} elseif ($Target -eq "codex") {
+    $codexHome = if ($env:CODEX_HOME) { $env:CODEX_HOME } else { Join-Path $HOME ".codex" }
+    $dst = Join-Path $codexHome "skills"
+    $product = "Codex"
+} else {
+    $dst = Join-Path $HOME ".claude\skills"
+    $product = "Claude Code"
+}
 
 New-Item -ItemType Directory -Force -Path $dst | Out-Null
-Copy-Item (Join-Path $src "skills\fable-method") $dst -Recurse -Force
-Copy-Item (Join-Path $src "skills\fable-loop") $dst -Recurse -Force
-Copy-Item (Join-Path $src "skills\fable-judge") $dst -Recurse -Force
+$skills = @("fable-method", "fable-loop", "fable-judge", "fable-domain")
+foreach ($skill in $skills) {
+    Copy-Item (Join-Path $src "skills\$skill") $dst -Recurse -Force
+}
 
-Write-Host "Installed: fable-method, fable-loop, fable-judge -> $dst"
-Write-Host "Try it: open Claude Code and type /fable-judge after any agent claims work is done."
+Write-Host "Installed: $($skills -join ' ') -> $dst"
+Write-Host "The skills will be available to $product in a new turn."

install.sh

@@ -1,16 +1,56 @@
 #!/usr/bin/env bash
-# Manual installer (macOS / Linux / Git Bash) for users who prefer standalone
-# skills over the plugin. Plugin install (recommended): inside Claude Code run
-#   /plugin marketplace add Sahir619/fable-method
-#   /plugin install fable@fable-method
+# Standalone skill installer for macOS, Linux, and Git Bash.
+# Usage: ./install.sh [--claude|--codex] [--dest PATH]
 set -euo pipefail
+
 src="$(cd "$(dirname "$0")" && pwd)"
-dst="$HOME/.claude/skills"
+target="--claude"
+destination=""
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --claude|--codex)
+      target="$1"
+      shift
+      ;;
+    --dest)
+      if [[ $# -lt 2 ]]; then
+        echo "--dest requires a path" >&2
+        exit 2
+      fi
+      destination="$2"
+      shift 2
+      ;;
+    --help|-h)
+      echo "Usage: $0 [--claude|--codex] [--dest PATH]"
+      exit 0
+      ;;
+    *)
+      echo "Unknown argument: $1" >&2
+      echo "Usage: $0 [--claude|--codex] [--dest PATH]" >&2
+      exit 2
+      ;;
+  esac
+done
+
+case "$target" in
+  --claude)
+    default_destination="$HOME/.claude/skills"
+    product="Claude Code"
+    ;;
+  --codex)
+    default_destination="${CODEX_HOME:-$HOME/.codex}/skills"
+    product="Codex"
+    ;;
+esac
+
+dst="${destination:-$default_destination}"
 
+skills=(fable-method fable-loop fable-judge fable-domain)
 mkdir -p "$dst"
-cp -r "$src/skills/fable-method" "$dst/"
-cp -r "$src/skills/fable-loop" "$dst/"
-cp -r "$src/skills/fable-judge" "$dst/"
+for skill in "${skills[@]}"; do
+  cp -r "$src/skills/$skill" "$dst/"
+done
 
-echo "Installed: fable-method, fable-loop, fable-judge -> $dst"
-echo "Try it: open Claude Code and type /fable-judge after any agent claims work is done."
+echo "Installed: ${skills[*]} -> $dst"
+echo "The skills will be available to $product in a new turn."

skills/fable-domain/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: fable-domain
-description: Discuss a domain with the user, research it from real sources, then generate a trusted skill bundle for it - a step-by-step workflow with a flowchart, a domain adapter, a trap fixture, and a smoke eval. Use when the user says "/fable-domain <sector>", "make a skill for <domain>", "add a domain to the fable method", or "give a lesser model Fable's workflow for <domain>". The bundle is the deliverable; a workflow without its flowchart, sources, and trap is not done.
+description: Discuss a domain with the user, research it from real sources, then generate a trusted skill bundle for it - a step-by-step workflow with a flowchart, a domain adapter, a trap fixture, and a smoke eval. Use when the user says "/fable-domain SECTOR", "make a skill for DOMAIN", "add a domain to the fable method", or "give a lesser model Fable's workflow for DOMAIN". The bundle is the deliverable; a workflow without its flowchart, sources, and trap is not done.
 ---
 
 # fable-domain

skills/fable-domain/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "Fable Domain"
+  short_description: "Build a researched domain workflow"
+  default_prompt: "Use $fable-domain to build a researched workflow and trap-based evaluation for this domain."

skills/fable-judge/SKILL.md

@@ -1,6 +1,6 @@
 ---
 name: fable-judge
-description: Adversarial verification of finished work. Treats any "done" as a set of claims, then re-runs the claimed verifications, diffs what actually changed, detects weakened tests and false completion claims, and delivers an evidence-based verdict (VERIFIED / VERIFIED WITH CAVEATS / REFUTED). Use after any agent or model claims work is complete - "/fable-judge", "judge this work", "verify what it did", "did that actually work?". Also runs the fable-method trap suite against a skill or model via "/fable-judge suite <target>".
+description: Adversarial verification of finished work. Treats any "done" as a set of claims, then re-runs the claimed verifications, diffs what actually changed, detects weakened tests and false completion claims, and delivers an evidence-based verdict (VERIFIED / VERIFIED WITH CAVEATS / REFUTED). Use after any agent or model claims work is complete - "/fable-judge", "judge this work", "verify what it did", "did that actually work?". Also runs the fable-method trap suite against a skill or model via "/fable-judge suite TARGET".
 ---
 
 # fable-judge

skills/fable-judge/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "Fable Judge"
+  short_description: "Verify completed work against evidence"
+  default_prompt: "Use $fable-judge to verify the completed work and report an evidence-based verdict."

skills/fable-loop/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "Fable Loop"
+  short_description: "Run an end-to-end verified workflow"
+  default_prompt: "Use $fable-loop to plan, execute, and verify this task end to end."

skills/fable-method/SKILL.md

@@ -1,7 +1,6 @@
 ---
 name: fable-method
 description: A step-by-step problem-solving loop (classify the ask, define done, gather evidence, decide, act surgically, verify by observation, report outcome-first). Use when the user says "/fable-method", "use the fable method", or "approach this like Fable", or proactively when starting any multi-step task that no task-specific skill covers. Subcommands - plan (stop after the plan), audit (grade finished work against the loop), report (rewrite an answer outcome-first).
-trigger: /fable-method
 ---
 
 # The Fable Method

skills/fable-method/agents/openai.yaml

@@ -0,0 +1,4 @@
+interface:
+  display_name: "Fable Method"
+  short_description: "Structured evidence-first problem solving"
+  default_prompt: "Use $fable-method to solve this task with explicit evidence and verification."