Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/bestagentkits/ck-skills/codexnpx skills add bestagentkits/ck-skills --skill codexgit clone --depth 1 https://github.com/bestagentkits/ck-skillsWrote 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/bestagentkits/ck-skills/codex)<a href="https://agentmods.dev/skills/bestagentkits/ck-skills/codex"><img src="https://agentmods.dev/badge/skills/bestagentkits/ck-skills/codex.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00126 | $0.02233 |
| Opus 5 | $0.00063 | $0.01117 |
| Sonnet 5 | $0.00025 | $0.00447 |
| Haiku 4.5 | $0.00013 | $0.00223 |
Grade B, and why
ck:codex scanned grade B with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Recursive force deletemediumDestructive command
rm -rf with a variable or a broad path is one typo away from removing the wrong tree.
mv ~/.codex/generated_images/"$latest_session"/* ./assets/ && rm -rf ~/.codex/generated_images/"$latest_session" Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.
How it starts
The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Codex CLI Skill
Use the codex CLI (OpenAI GPT-5.5 + GPT-5.4 Image 2) as a complementary tool to Claude. Codex's strengths are careful file reading, edge-case spotting, role-play fidelity, and unlimited high-quality image generation under subscription auth.
When To Use Codex (Decision Tree)
User intent
├── "Review/audit my code/PR/diff" → Codex review (see references/code-review-workflows.md)
├── "Audit/review my plan or spec" → Codex plan audit (see references/plan-audit-workflows.md)
├── "Generate an image/banner/illustration/icon/infographic/visual asset" → Codex image gen (see references/image-generation.md)
├── "Get a second opinion from Codex" → Codex exec one-shot
├── "Pretend to be Gemini/Qwen/o3" → Codex role-play (see references/best-practices.md)
└── "Just run codex on X programmatically" → Codex exec (see references/cli-reference.md)
Do NOT use Codex when:
- The task is small, mechanical, or fully solvable by Claude in the current session (waste of latency/credits).
- The user wants a final implementation pushed to disk by Codex — prefer Claude for in-session edits, use Codex for analysis only unless explicitly asked.
- Sensitive data is in the working dir without user clearance (Codex sends content to OpenAI).
Why Codex Beats Claude For Certain Tasks
| Task | Why Codex |
|---|---|
| Plan/spec audit | Codex (GPT-5.5) reads files carefully — catches edge cases Opus skims. Uses ~4× fewer tokens than Claude on equivalent work |
| PR review | Independent reader, fresh context, no shared bias with the implementing Claude session. Native GitHub integration via @codex review |
| Image generation | gpt-image-2 (announced Oct 2025) via subscription counts toward limits but no per-image dollar charge; iterate fast in terminal. Field reports prefer it over Gemini Nano Banana Pro for mockups/decorations/banners. Invoke via bundled $imagegen skill. Native transparency NOT supported — uses official chroma-key workflow (see image-generation.md) |
| Style/persona prompting | Persona instructions in AGENTS.md or one-off prompts shift Codex's voice/verbosity reliably. Cross-model mimicry (Codex behaving as Gemini/Qwen/o3) is community-reported but unverified — use for prompt iteration only, not production routing |
What ships with it
9 files 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.
- references/best-practices.md 8.3 KB
- references/cli-reference.md 4.1 KB
- references/code-review-workflows.md 4.7 KB
- references/image-generation.md 7.9 KB
- references/plan-audit-workflows.md 3.8 KB
- scripts/codex-audit-plan.sh 1.7 KB runs code
- scripts/codex-generate-image.sh 2.8 KB runs code
- scripts/codex-review-pr.sh 1.5 KB runs code
- scripts/codex-strip-chroma-key.sh 1.5 KB runs code
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.
- 5d ago First seen · 121 lines · 126 tokens per session scan B 2c86e1ff413e
ck:codex is a skill published in the GitHub repository bestagentkits/ck-skills (6 stars, last pushed 3mo ago), licensed MIT. It adds 126 tokens to every session and 2,233 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it B with 1 finding (recursive force delete). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
frontend-design
Guidance for distinctive, intentional frontend/UI design — aesthetic direction, typography, layout, motion, and copy — when building new UI or reshaping existing UI. Gates by scope before designing: a light/surgical change (one component, one page section, extending an existing design system) gets inline design…
docs-consolidate
Audit a repo's documentation for internal contradictions, stale claims, orphans and bloat after it has accumulated commits, then report findings for the user to disposition. Use when the consolidation nudge fires, or when the user asks to consolidate, audit, or spring-clean the docs. Triggers: "/docs-consolidate"…
retro
Run an interactive session retrospective. Reads the per-session event log (maintained by the PostToolUse hook) and uses git diff/status/log as memory primer, then walks through specific moments via adaptive questions driven by what changed, and writes structured native memory entries. Suggest this when the end-of-day…
adr
Use when the user knows what they want built and says "/adr", "write an ADR for X", "decide and build X", or "ADR-driven". Turns an intent into a grounded, cited, build-ready ADR at docs/adr/YYYY-MM-DD- .md — load-bearing decisions surfaced to the human — then hands off to nightshift:plan's landing step (the plan is…
plan
Use when the user has an idea, feature, or fix that is more than a one-sitting edit and says "plan this", "write a plan for X", "/nightshift:plan", or "what would it take to build X". Sizes the work (trivial → no artifact; medium → a lean plan; large → a short spec first), asks one question at a time until the design…
domain-modeling
Use when pinning down domain terminology, building a ubiquitous language or project glossary, disambiguating overloaded or vague terms, or maintaining a CONTEXT.md — or when another skill needs to sharpen the domain model. Do NOT use for recording architectural decisions (use adr) or for writing implementation specs.