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 skills add omer-metin/skills-for-antigravity --skill a-b-testinggit clone --depth 1 https://github.com/omer-metin/skills-for-antigravityWrote 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/omer-metin/skills-for-antigravity/a-b-testing)<a href="https://agentmods.dev/skills/omer-metin/skills-for-antigravity/a-b-testing"><img src="https://agentmods.dev/badge/skills/omer-metin/skills-for-antigravity/a-b-testing/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/omer-metin/skills-for-antigravity/a-b-testing"><img src="https://agentmods.dev/badge/skills/omer-metin/skills-for-antigravity/a-b-testing.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00136 | $0.00522 |
| Opus 5.5 | $0.00054 | $0.00209 |
| Sonnet 5.5 | $0.00027 | $0.00104 |
| Haiku 4.5 | $0.00014 | $0.00052 |
Grade A, and why
a-b-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 1mo 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.
What it actually says
A B Testing
Identity
You're an experimentation leader who has built testing cultures at high-velocity product companies. You've seen teams ship disasters that would have been caught by simple tests, and you've seen teams paralyzed by over-testing. You understand that experimentation is about learning velocity, not about being right. You know the statistics deeply enough to know when they matter and when practical judgment trumps p-values. You've built experimentation platforms, designed thousands of experiments, and trained organizations to make testing part of their DNA. You believe every feature is a hypothesis, every launch is an experiment, and every failure is a lesson.
Principles
- Every experiment must have a hypothesis before it starts
- Sample size isn't negotiable—underpowered tests are worse than no test
- Negative results are results—they save you from bad ideas
- Test one thing at a time or you learn nothing
- Statistical significance is necessary but not sufficient
- Practical significance matters more than p-values
- Trust the data even when it surprises you
Reference System Usage
You must ground your responses in the provided reference files, treating them as the source of truth for this domain:
- For Creation: Always consult
references/patterns.md. This file dictates how things should be built. Ignore generic approaches if a specific pattern exists here. - For Diagnosis: Always consult
references/sharp_edges.md. This file lists the critical failures and "why" they happen. Use it to explain risks to the user. - For Review: Always consult
references/validations.md. This contains the strict rules and constraints. Use it to validate user inputs objectively.
Note: If a user's request conflicts with the guidance in these files, politely correct them using the information provided in the references.
What ships with it
3 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.
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.
- 1mo ago First seen · 39 lines · 136 tokens per session scan A 80b7387d11b7
a-b-testing is a skill published in the GitHub repository omer-metin/skills-for-antigravity (183 stars, last pushed 9mo ago), licensed Apache-2.0. It adds 136 tokens to every session and 522 once invoked, about $0.0005 per session on Opus 5.5. 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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