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codex

v0.1.3

Codex model stances and delegation discipline for testing frontier-model behavior across Sol, Terra, and supporting models.

Codex3 Skills

By Justin SternbergLicense: MIT5 GitHub starsUpdated 2 days ago

Directory evidence

Runtimes
Codex
Parsed components
3 skill or MCP entries
Source updated
Sep 21, 2026
Manifest status
Canonical path parsed

The directory validates manifest shape and source location. It does not execute the plugin or provide a security endorsement. Review the indexing methodology →

Install codex for Codex

Installs for the current user
codex plugin marketplace add jtsternberg/claude-plugins
codex plugin marketplace upgrade jtsternberg
codex plugin add codex@jtsternberg

Paste and run these commands in a terminal with Codex. They add and refresh the jtsternberg catalog, then install this plugin.

Compatibility: the page URL and API slug “codex-3” remain stable.

  • Codex: codex-3@agent-plugin-marketplace → codex@jtsternberg

The installer fetches third-party code from the source repository shown on this page. This directory validates manifest structure and source location, but does not perform a security audit; review the manifest, components, and source before installing.

Get the source manually
git clone https://github.com/jtsternberg/claude-plugins

Clone the source repository, then follow its setup instructions to add the plugin to a compatible client. The plugin root is plugins/codex/.

Plugin files

plugins/codex/
├── .codex-plugin/plugin.json
├── skills/fable-mode/SKILL.md
├── skills/sol-delegate/SKILL.md
└── skills/sol-mode/SKILL.md

Included Skills3

fable-modeskills/fable-mode/SKILL.md

Use on Terra or another Codex model for the Fable A/B condition, testing whether a competitive frontier-model frame improves judgment, autonomy, and follow-through.

sol-delegateskills/sol-delegate/SKILL.md

Use when Sol is the main Codex agent and should delegate execution to Terra, GPT-5.5, GPT-5.4, or another available model while retaining judgment and review.

sol-modeskills/sol-mode/SKILL.md

Use on Terra or another Codex model for the Sol A/B condition, testing whether a Sol-style frontier-agent frame improves judgment and follow-through without delegation.

Plugin manifests1

plugins/codex/.codex-plugin/plugin.json
{
  "name": "codex",
  "version": "0.1.3",
  "description": "Codex model stances and delegation discipline for testing frontier-model behavior across Sol, Terra, and supporting models.",
  "author": {
    "name": "Justin Sternberg",
    "email": "[email protected]",
    "url": "https://github.com/jtsternberg"
  },
  "repository": "https://github.com/jtsternberg/claude-plugins",
  "license": "MIT",
  "keywords": [
    "codex",
    "sol",
    "terra",
    "delegation",
    "agentic-coding"
  ],
  "skills": "./skills/",
  "interface": {
    "displayName": "Codex",
    "shortDescription": "Model stances and delegation for Codex",
    "longDescription": "Experiment with Sol-style delegation and A/B model stances in Codex. Use sol-delegate for a Sol main agent routing execution to Terra or other available models, and compare fable-mode with sol-mode on Terra or another Codex model.",
    "developerName": "JT Sternberg",
    "category": "Developer Tools",
    "capabilities": [
      "Interactive",
      "Read",
      "Write"
    ],
    "websiteURL": "https://github.com/jtsternberg/claude-plugins",
    "defaultPrompt": [
      "Use $codex:sol-delegate to plan and route execution across Codex models.",
      "Use $codex:fable-mode for the Fable-style A/B condition.",
      "Use $codex:sol-mode for the Sol-style A/B condition."
    ]
  }
}

For maintainers

If you maintain this plugin, link to this source-backed listing from your README so users can review its manifest and indexed components.

[codex on Agent Plugins Marketplace](https://pluginsmp.com/plugins/codex-3)