Ab Test Design Brief

What it does

When your agent uses it

• Planning an A/B test from a product idea
• Writing an experiment spec
• Defining test/control variants
• Choosing metrics

Example prompts

• “/ab-test-design-brief”

Requirements

• Compatibility (from SKILL.md): Codex, Claude Code, and other Agent Skills-compatible clients.

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

1. 1State the product decision the test must inform.
2. 2Write a hypothesis with observation, predicted change, audience, and metrics.
3. 3Choose one primary success metric plus guardrail metrics.
4. 4Establish the baseline or explain why a proxy metric is being used.
5. 5Define eligibility, exposure, test variant, and control variant.
6. 6Choose the randomization unit that preserves a coherent user experience.
7. 7Record confidence requirements, sample-size assumptions, and launch criteria.

What it can do on your machine

Read from SKILL.md and the folder at commit 3e1456a. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are markdown).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

• Compatibility

  Codex, Claude Code, and other Agent Skills-compatible clients.

  From compatibility in the SKILL.md frontmatter.

Context cost

Ab Test Design Brief loads about 890 tokens when it runs, and up to ~2.5k if it reads all its reference files. Until then it costs about 93 tokens; SKILL.md has 277 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~93

When it runs · the whole SKILL.md, loaded when a task matches

~890

With references · SKILL.md plus every file in references/, read only if the agent opens them

~2.5k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from hashgraph-online/awesome-codex-plugins at commit 3e1456a, republished under its MIT licence (© hashgraph-online). 277 words, ~890 tokens.

name

ab-test-design-brief

description

Build product A/B test briefs with hypotheses, success metrics, guardrails, baselines, proxy metrics, eligibility, variants, randomization, confidence, and launch criteria. Use when planning an A/B test from a product idea, writing an experiment spec, defining test/control variants, choosing metrics, or checking whether an experiment is ready to run.

compatibility

Codex, Claude Code, and other Agent Skills-compatible clients.

license

MIT

metadata.version

0.1.0

metadata.displayName

A/B Test Design Brief

metadata.category

Product Management

metadata.tags

practical-ab-testing,ab-testing,experimentation,product-analytics,metrics

# A/B Test Brief

## Decision
[What decision this test will support.]

## Hypothesis
Because [observation], we believe [change] will cause [outcome] for [audience].
We will know this is true when [primary metric] changes without harming [guardrails].

## Metrics
| Metric | Role | Baseline | Target or Concern | Data Source |
|--------|------|----------|-------------------|-------------|

## Variants and Eligibility
- Population:
- Eligibility criteria:
- Exposure event:
- Control:
- Test:
- Randomization unit:

## Confidence Plan
- Minimum detectable effect:
- Sample size or duration:
- Risks to validity:

## Launch Criteria
- Ship if:
- Do not ship if:
- Investigate if:

© hashgraph-online, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 5 other files (references) in plugins/LVTD-LLC/skills/skills/ab-test-design-brief of hashgraph-online/awesome-codex-plugins.

• SKILL.md
• guidelines.md
• references/core/examples.md
• references/core/knowledge.md
• references/core/rules.md
• workflows/create-ab-test-brief.md

Open the folder on GitHubat commit 3e1456a