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/oliver-kriska/claude-elixir-phoenix/codex-loopnpx skills add oliver-kriska/claude-elixir-phoenix --skill codex-loopgit clone --depth 1 https://github.com/oliver-kriska/claude-elixir-phoenixWrote 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/oliver-kriska/claude-elixir-phoenix/codex-loop)<a href="https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/codex-loop"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/codex-loop.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 5.1 | $0.00052 | $0.01412 |
| Opus 5 | $0.00026 | $0.00706 |
| Sonnet 5 | $0.00010 | $0.00282 |
| Haiku 4.5 | $0.00005 | $0.00141 |
Grade A, and why
codex-loop 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 3d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- phx-codex-loop — 89% identical, 40 lines differ
How it starts
The opening of the file, as written. The whole thing — 130 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Codex Loop (fix until clean)
Critic→Refiner loop with the Codex CLI as external critic: review → fix
approved findings → verify → re-review, until codex is clean or rounds run
out. Codex reviews; Claude fixes. Complements /phx:review (Claude panel)
— run either or both before a PR.
Usage
/phx:codex-loop # diff vs default branch, interactive
/phx:codex-loop --uncommitted # staged + unstaged + untracked
/phx:codex-loop --base develop # explicit base branch
/phx:codex-loop --auto # auto-approve P0/P1/P2, skip P3
/phx:codex-loop --max-rounds 2 # default 3
Iron Laws
- BOUNDED rounds — never exceed --max-rounds (default 3) — each round costs codex quota; report remaining findings instead of looping on
- Verify BEFORE re-review —
mix compile --warnings-as-errors+ tests must pass before burning a codex round on broken code - NEVER commit or push — leave git to the user
- Codex findings get Iron Law scrutiny — decline suggestions that violate an Iron Law, with explanation in the round report
- Skipped findings are reported, never dropped — every finding ends as fixed, declined (with reason), or deferred-by-user
- Missing CLI stops the skill with an install hint — suggest
/phx:reviewas the codex-free alternative; never crash
Workflow
Step 1: Preflight
Run command -v codex. If missing: STOP.
Show the install hint (brew install codex or npm i -g @openai/codex,
then codex login; codex doctor to diagnose) and suggest /phx:review.
Then two cheap checks that save review rounds:
- Dirty tree (
git status --short, only when using--base): codex inspects working-tree state too and WILL flag local dirt (stray edits, dirty submodules) as findings. Surface the dirt and ask: clean/stash first, or proceed knowing round 1 may spend findings on it. - Missing rubric: if
AGENTS.mdhas no## Review guidelinessection, note once that/phx:initinstalls the Elixir rubric that steers codex priorities — then proceed (it works without, on defaults).
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.
- 3d ago First seen · 130 lines · 52 tokens per session scan A 25024770b147
codex-loop is a skill published in the GitHub repository oliver-kriska/claude-elixir-phoenix (538 stars, last pushed yesterday), licensed MIT. It adds 52 tokens to every session and 1,412 once invoked, about $0.0003 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 2026-09-03.
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