Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/majiayu000/claude-skill-registrynpx agentmods add skills/majiayu000/claude-skill-registry/add-codexWrote 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.
[](https://agentmods.dev/skills/majiayu000/claude-skill-registry/add-codex)<a href="https://agentmods.dev/skills/majiayu000/claude-skill-registry/add-codex"><img src="https://agentmods.dev/badge/skills/majiayu000/claude-skill-registry/add-codex/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/majiayu000/claude-skill-registry/add-codex"><img src="https://agentmods.dev/badge/skills/majiayu000/claude-skill-registry/add-codex.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 2 findings, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Data Exfiltration · line 121 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Rogue Agent · line 140 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00076 | $0.02143 |
| Opus 5 | $0.00038 | $0.01071 |
| Sonnet 5 | $0.00015 | $0.00429 |
| Haiku 4.5 | $0.00008 | $0.00214 |
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 11d 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.
How it starts
The opening of the file, as written. The whole thing — 162 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Codex agent provider
NanoClaw runs agents in a long-lived poll loop inside the container. The backend is selected with AGENT_PROVIDER (claude | opencode | codex | mock).
Trunk ships with only the claude provider baked in. This skill copies the Codex provider files in from the providers branch, wires them into the host and container barrels, updates the Dockerfile to install the Codex CLI, and rebuilds the image.
The Codex provider runs codex app-server as a child process and speaks JSON-RPC over stdio. That gives it native session resume, streaming events, MCP tool access, and thread/compact/start compaction — same feature bar as the Claude Agent SDK, without the Anthropic-only lock-in.
Install
Pre-flight
If all of the following are already present, skip to Configuration:
src/providers/codex.tscontainer/agent-runner/src/providers/codex.tscontainer/agent-runner/src/providers/codex-app-server.tscontainer/agent-runner/src/providers/codex.factory.test.tsimport './codex.js';line insrc/providers/index.tsimport './codex.js';line incontainer/agent-runner/src/providers/index.tsARG CODEX_VERSIONand"@openai/codex@${CODEX_VERSION}"in the pnpm global-install block incontainer/Dockerfile
Missing pieces — continue below. All steps are idempotent; re-running is safe.
1. Fetch the providers branch
git fetch origin providers
2. Copy the Codex source files
Wholesale copies (owned entirely by this skill — user edits to these files won't survive a re-run, as designed):
git show origin/providers:src/providers/codex.ts > src/providers/codex.ts
git show origin/providers:container/agent-runner/src/providers/codex.ts > container/agent-runner/src/providers/codex.ts
git show origin/providers:container/agent-runner/src/providers/codex-app-server.ts > container/agent-runner/src/providers/codex-app-server.ts
git show origin/providers:container/agent-runner/src/providers/codex.factory.test.ts > container/agent-runner/src/providers/codex.factory.test.ts
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.
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.
- 11d ago First seen · 162 lines · 76 tokens per session scan A 3e4d53e33d29
add-codex is a skill published in the GitHub repository majiayu000/claude-skill-registry (600 stars, last pushed today), licensed MIT. It adds 76 tokens to every session and 2,143 once invoked, about $0.0004 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.
Other skills, from other repositories
remotion-docs
Search and fetch Remotion documentation pages.
remotion-render
Best practices for rendering videos.
remotion-saas
Building video apps with Remotion - framework, rendering and Player advice.
remotion-maps
Remotion Map animation knowledge.
mediabunny
Multimedia handling with the Mediabunny library.
task-observer
Monitors task execution for skill improvement opportunities. Use during ANY multi-step task, agentic workflow, or work session where the agent uses tools and produces deliverables. Captures patterns, user corrections, workflow insights, and methodology worth preserving as reusable skills. Also triggers in post-task…