add-codex

add-codex is a skill for Claude Code from nanocoai/nanoclaw. It costs 91 tokens per session (1,952 once invoked), scanned A, original, MIT.

An agent-provider add-on that lets NanoClaw use OpenAI Codex as its coding agent, alongside or instead of Claude. It supports planning, tool use, and resuming conversations.

In plain words
What is it for?
Use it to configure Codex as the backend for selected NanoClaw groups, authenticate with a ChatGPT subscription or OpenAI API key, and resume server-side conversations.
Why use it?
It lets you choose Codex for particular agent groups without replacing the rest of your setup. Credentials stay outside the container and are supplied when needed.

Skill for Claude Code

Written for Claude Code: SessionStart hook event. Also seen: mentions AGENTS.md; mentions Codex.

Not installable on its own: it runs a file from its repository that does not travel with it. Clone the repository, or install whatever ships that file. The line is ./container/build.sh.

About the project

NanoClaw is an AI assistant that runs agents inside separate Linux containers, isolating their files and execution environments. People use it to connect agents to messaging services and run assistants with memory and scheduled jobs. The catalogue contains skills and instructions for extending or operating NanoClaw.

nanocoai/nanoclaw · 30,703 stars · on GitHub · nanoclaw.dev

Install

Getting it into your agent

There is no command for this one: it runs only inside a plugin, and the catalogue could not identify which plugin ships it. The source is linked below.

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for add-codex

README.md
[![agentmods](https://agentmods.dev/badge/skills/nanocoai/nanoclaw/add-codex.svg)](https://agentmods.dev/skills/nanocoai/nanoclaw/add-codex)
Your own site
<a href="https://agentmods.dev/skills/nanocoai/nanoclaw/add-codex"><img src="https://agentmods.dev/badge/skills/nanocoai/nanoclaw/add-codex.svg" alt="Measured on agentmods" height="20"></a>
Per session 91 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,952 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00091 $0.01952
Opus 5 $0.00046 $0.00976
Sonnet 5 $0.00018 $0.00390
Haiku 4.5 $0.00009 $0.00195

Measured 6d ago against content hash b232002628bd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

add-codex scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/add-codex/SKILL.md · 144 lines

How it starts

The opening of the file, as written. The whole thing — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Codex agent provider

Shortcut: pnpm exec tsx setup/index.ts --step provider-auth codex performs this whole install (manifest-driven from the providers branch: files, barrels, CLI manifest entry, image rebuild) plus auth in one command. The steps below are the same operations, for agent-driven or manual application.

NanoClaw selects each group's agent backend from container_configs.provider (default claude). This skill installs the Codex provider: copy the payload from the providers branch, append one import to each of the three provider barrels, add the pinned Codex CLI to the container manifest (container/cli-tools.json), rebuild, then run the vault auth walk-through.

The provider runs codex app-server as a child process speaking JSON-RPC over stdio: native streaming, MCP tools, server-side conversation history (the continuation is a thread id, no on-disk transcript). Credentials are vault-only: OneCLI serves a sentinel auth.json stub into the container and swaps the real ChatGPT token or API key on the wire — no key in .env, nothing readable in the container.

The mechanical steps under Install carry nc: directive fences: an agent reads the prose and applies them, and a parser can apply them deterministically from the same document. Every directive is idempotent, so the whole skill is safe to re-run; anything a parser can't apply falls back to the prose beside it.

Install

Pre-flight

Requires src/project-doc-compose.ts on trunk. If it is missing, stop and tell the operator to run /update-nanoclaw first.

Check whether the payload is already wired (a prior apply, or a trunk that still carries it). All of these present means installed — skip to Authenticate:

  • src/providers/codex.ts and src/providers/codex-agents-md.ts
  • container/agent-runner/src/providers/codex.ts and codex-app-server.ts
  • setup/providers/codex.ts
  • import './codex.js'; in src/providers/index.ts, container/agent-runner/src/providers/index.ts, and setup/providers/index.ts
  • an @openai/codex entry in container/cli-tools.json

Read the full file on GitHub · 144 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 144 lines · 91 tokens per session scan A b232002628bd

Subscribe to this mod's changes

add-codex is a skill published in the GitHub repository nanocoai/nanoclaw (30,703 stars, last pushed yesterday), licensed MIT. It adds 91 tokens to every session and 1,952 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.