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 bromso/metapowers --skill ab-test-setupgit clone --depth 1 https://github.com/bromso/metapowersWrote 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/bromso/metapowers/ab-test-setup)<a href="https://agentmods.dev/skills/bromso/metapowers/ab-test-setup"><img src="https://agentmods.dev/badge/skills/bromso/metapowers/ab-test-setup/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/bromso/metapowers/ab-test-setup"><img src="https://agentmods.dev/badge/skills/bromso/metapowers/ab-test-setup.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 | $0.00059 | $0.00805 |
| Opus 5.5 | $0.00024 | $0.00322 |
| Sonnet 5.5 | $0.00012 | $0.00161 |
| Haiku 4.5 | $0.00006 | $0.00081 |
Grade A, and why
ab-test-setup scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 61 lines — stays where its author put it; the contents beside it link to each section on GitHub.
A/B Test Setup
Design rigorous A/B tests for "$ARGUMENTS". Create testable hypotheses, define variants, calculate sample sizes, and plan measurement.
Arguments. $ARGUMENTS may contain the project name and optional flags. Take the first token as <project> and treat --skip-checks as a flag; never include flags in file paths. All paths below use <project>. If --skip-checks is present, skip the prerequisite check and, before writing any artifact, append one line to .metapowers/marketing/<project>/skip-log.md: - <ISO timestamp> — <skill name> skipped prerequisite check for <artifact file> — reason: <reason or "none given">.
Prerequisites
Read .metapowers/marketing/<project>/00-strategy.md. If this file does not exist, tell the user:
Phase 0 (Strategy) has not been completed for "". Run
/marketing:customer-research <project>first, or use--skip-checksto bypass.
Process
-
Read context:
- Read
.metapowers/marketing/<project>/00-strategy.mdfor business context - Read
.metapowers/marketing/<project>/02-act.mdand.metapowers/marketing/<project>/03-convert.mdif they exist (for CRO recommendations that need testing)
- Read
-
Define the test:
- What are you testing? (headline, CTA, layout, pricing, flow)
- Hypothesis format: "If we [change], then [metric] will [improve/decrease] by [amount], because [rationale]"
- Primary metric (one clear success metric)
- Secondary metrics (guard-rail metrics to watch)
-
Design variants:
- Control (A): current experience
- Treatment (B): specific change — one variable only
- If multivariate: document variable matrix
- Screenshots or mockups of each variant
-
Statistical planning:
- Current baseline metric (conversion rate, click rate, etc.)
- Minimum detectable effect (MDE): what improvement is meaningful?
- Required sample size calculation
- Expected test duration based on traffic
- Statistical significance threshold (typically 95%)
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 · 61 lines · 59 tokens per session scan A 2205669a96c9
ab-test-setup is a skill published in the GitHub repository bromso/metapowers (2 stars, last pushed 3d ago), licensed MIT. It adds 59 tokens to every session and 805 once invoked, about $0.0002 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 2026-10-21.
Other skills, from other repositories
design-method
Use when starting any design task — resolves register, sets the 3 dials, locks Gate 0, and routes to the right move and target skill.
design-webapp
Use when building or extending a dashboard, SaaS screen, or any authenticated app surface — use design-web instead for a marketing site.
react-tanstack-router
Use when implementing routing in a React app (NOT Next.js) with TanStack Router — file-based routes, loaders, search params.
fusecore
Use when creating modules, understanding FuseCore structure, or implementing features in a FuseCore modular-monolith Laravel project.
laravel-billing
Use when implementing subscriptions, invoices, payment methods, webhooks, or billing portals with Laravel Cashier (Stripe or Paddle).
laravel-permission
Use when implementing RBAC, role-based access control, or user authorization with Spatie Laravel Permission.