code-review-testing

A testing guideline for changes to coding-agent logic, recommending integration tests that run against a test instance of Codex.

In plain words
What is it for?
Use it when adding agent features or behavior changes to identify required tests and place them in the expected test suites.
Why use it?
It helps catch problems in real agent behavior that isolated unit tests may miss.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/openai/codex/code-review-testing
Any agent
npx skills add openai/codex --skill code-review-testing
Clone the repo
git clone --depth 1 https://github.com/openai/codex

Made for: Claude Code, Codex.

Per session 8 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 122 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 $0.00008 $0.00122
Opus 5 $0.00004 $0.00061
Sonnet 5 $0.00002 $0.00024
Haiku 4.5 $0.00001 $0.00012

Measured 2d ago against content hash 7722784fda70, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-review-testing 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 2d 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.

Origin

Copies of this mod

8 near-identical copies found in the catalogue:

.codex/skills/code-review-testing/SKILL.md · 15 lines

What it actually says

For agent changes prefer integration tests over unit tests. Integration tests are under core/suite and use test_codex to set up a test instance of codex.

Features that change the agent logic MUST add an integration test:

  • Provide a list of major logic changes and user-facing behaviors that need to be tested.

If unit tests are needed, put them in a dedicated test file (*_tests.rs). Avoid test-only functions in the main implementation.

Check whether there are existing helpers to make tests more streamlined and readable.

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. 2d ago First seen · 15 lines · 8 tokens per session scan A 7722784fda70

Subscribe to this mod's changes

code-review-testing is a skill published in the GitHub repository openai/codex (120,598 stars, last pushed today), licensed Apache-2.0. It adds 8 tokens to every session and 122 once invoked, about $0.0000 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.

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