About
Lean Codex-only agent toolkit for ChatGPT Plus
README
HolyCodex is a modified, standalone Codex-only hard fork of oh-my-openagent. It keeps the parts that make Codex better at software work, removes the OpenCode runtime and organizational agent machinery, and compresses persistent instructions for lower ChatGPT Plus usage.
What
HolyCodex installs one focused Codex toolkit:
- 16 on-demand skills for programming, debugging, frontend, LSP, AST search, security research, planning, handoffs, goal definition, compression, and related workflows.
- Three optional subagents:
explorerfor internal inspection,librarianfor external research, andworkerfor bounded implementation. - Three MCP defaults:
git_bash,lsp, andcontext7. - Small command hooks for readiness and scoped rules.
- A Node-compatible installer and prebuilt runtime usable through npm or Bun.
The primary agent owns intent, scope, architecture, decisions, integration, and final verification. Subagents only reduce cost on narrow independent work; skills own their declared methods and gates.
Why
Large always-on prompts, agent hierarchies, review loops, and duplicated context consume tokens before useful work begins. HolyCodex takes a smaller approach:
- Skills load only when descriptions match the task and state activation, exclusions, outcome, and adjacent boundary.
- Rules are path-scoped, size-limited, cached, and deduplicated;
AGENTS.mdis never reinjected. - Concurrent delegation is capped at two; every delegated slice has fixed scope, evidence, acceptance, and stop conditions under primary-agent control.
- Explorer and librarian use GPT-5.6 Luna low; worker uses GPT-5.6 Luna medium.
- Git Bash shell execution is required only on native Windows when its MCP run tool is available; other environments use their native shell directly.
- OMO workflows and retained references are rewritten with caveman-style token efficiency.
- The OMO frontend skill is merged with GPT Taste instead of shipping another overlapping skill.
The result aims to keep strong engineering behavior while spending fewer Plus tokens on ceremony and repeated instructions.
How
Install
Use either runtime:
npx holycodex install
bunx holycodex install
Installation is noninteractive. It:
- Backs up every affected existing file or managed cache under the OS temporary directory.
- Removes legacy OMO configuration and cache after backup.
- Preserves unrelated Codex settings and explicit model or agent preferences.
- Installs the HolyCodex marketplace, plugin, agents, skills, hooks, and MCP definitions.
- Sets
max_concurrent_threads_per_session = 2and defaults the root model to GPT-5.6 Sol low only when no root preference exists.
Codex may still ask you to review and trust the installed command hooks. This security review is the only manual installation step.
Options:
holycodex install --json
holycodex install
holycodex --help
holycodex --version
Cleanup
npx holycodex cleanup
# or
bunx holycodex cleanup
Cleanup backs up affected files, removes only HolyCodex-owned configuration and artifacts, and preserves unrelated settings. Install and cleanup are idempotent.
Repository layout
plugin/skills/— shipped skill catalogue and on-demand references.plugin/agents/— the three cost-focused subagent definitions.plugin/hooks/— supported command hooks for readiness and scoped rules.plugin/.mcp.json— local and remote MCP defaults.plugin/runtime/— prebuilt Node-compatible CLI, rules, Git Bash, and LSP runtime.src/— installer, cleanup, bootstrap, and scoped-rules source.packages/— Git Bash and LSP MCP source.test/— CLI, lifecycle, catalogue, rules, bootstrap, and MCP tests.
Thanks
HolyCodex exists because of the work of:
- YeonGyu Kim and the oh-my-openagent contributors, whose project, history, workflows, and Codex integrations form the foundation of this hard fork.
- Julius Brussee and caveman contributors, for the token-efficient communication approach adapted here.
- The authors credited in plugin/skills/frontend/ATTRIBUTION.md, whose frontend design, performance, and UI/UX resources remain attributed under their original terms.
- Every upstream library and tool author whose work is preserved in the Git history and third-party notices.
Licenses
HolyCodex uses the same Sustainable Use License 1.0 as oh-my-openagent. This is not the MIT License: use and distribution are subject to the limitations in LICENSE.md.
Third-party components retain their original licenses. Relevant notices and bundled license files are preserved in THIRD-PARTY-NOTICES.md and alongside the applicable skills or components.
Install Holycodex in Claude Desktop, Claude Code & Cursor
unyly install holycodexInstalls into Claude Desktop, Claude Code, Cursor & VS Code — handles npx, uvx and build-from-source repos for you.
First time? Get the CLI: curl -fsSL https://unyly.org/install | sh
Or configure manually
Run in your terminal:
claude mcp add holycodex -- npx -y holycodexFAQ
Is Holycodex MCP free?
Yes, Holycodex MCP is free — one-click install via Unyly at no cost.
Does Holycodex need an API key?
No, Holycodex runs without API keys or environment variables.
Is Holycodex hosted or self-hosted?
Self-hosted: the server runs locally on your machine via the install command above.
How do I install Holycodex in Claude Desktop, Claude Code or Cursor?
Open Holycodex on unyly.org, pick your client tab (Claude Desktop, Claude Code, Cursor) and press Install — the config is generated automatically, no JSON editing.
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